Sandy Bridge maximum vcore for 24/7 use

I have done quite a bit of reading on this and there does not seem to be any definitive information regarding the maximum vcore for sandy bridge that is appropriate for 24/7 use. Opinions seem to vary pretty widely. On one hand there are "guidelines" stating to keep it below 1.35, and on the other hand there are technical reps from a motherboard maker which imply that 1.42 is a fine starting point and that up to 1.52 is ok so long as temperatures are under control. The same source stated that Intel told him/her that 1.57 definitely will cause degradation.

I was wondering if anyone has definitive information on this topic based on hard facts from a reputable source.

I apologize in advance if this issue has been previously settled in another thread.

1.375v

1.57v *will* definitely cause degradation. It's already happened to C_N and even the author of the UD7 overclocking guide. This is a 32nm chip you're talking about here... The only way you're going to avoid damage at such high voltages is with subzero or LN2.

1.35v is DEFINITELY the upper fully safe limit which shouldn't cause anyone any problems whatsoever, but the question is, is going up to 1.45v going to be safe long term or not. The chips are still too new (they've been out less than a month) to know the answer to that at the moment, so you just have to wait and see if vcores between 1.35-1.45v are going to be safe as long as you keep the temps down.

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Originally Posted by Metroid

1.375v

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I'd agree with that..Maybe even 1.4..Maybe
I use 1.325vcore for 4634MHz 24/7 100% load on air with temps in the mid 50's

Listen to the manufacturers. It's funny how people just come out with all sort of "max number" for each voltages without any proof. It was CPU PPL for 65nm and 45nm CPUs and the next was max i7 vCore and so on. Many experienced OCers proved them wrong by going really high values for months with any degradation with countless setups. Each major manufacturer has their lab and they have far better grasp and knowledge than average joes who blindly state numbers such as 1.35 as "max". Asus and Intel said if you go over 1.55, you'll start to see some degradation.

It's your choice to be over-cautious but just remember this, between 65nm, 45nm, and 32nm, there aren't any differences in max vCore recommendation from Intel. nm differences can't be measured by mere .01 volt.

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Originally Posted by Movieman

I'd agree with that..Maybe even 1.4..Maybe
I use 1.325vcore for 4634MHz 24/7 100% load on air with temps in the mid 50's

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Is that BIOS or load in windows?

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Originally Posted by deaffob

Listen to the manufacturers. It's funny how people just come out with all sort of "max number" for each voltages without any proof. It was CPU PPL for 65nm and 45nm CPUs and the next was max i7 vCore and so on. Many experienced OCers proved them wrong by going really high values for months with any degradation with countless setups. Each major manufacturer has their lab and they have far better grasp and knowledge than average joes who blindly state numbers such as 1.35 as "max". Asus and Intel said if you go over 1.55, you'll start to see some degradation.

It's your choice to be over-cautious but just remember this, between 65nm, 45nm, and 32nm, there aren't any differences in max vCore recommendation from Intel. nm differences can't be measured by mere .01 volt.

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I would respectfully disagree. I remember well when the first 45nm Yorkies came out and people treated then the same as the 65nm Kentsfields and we had a rash of dead chips on the forum.
1.4vcore with 1.45VTT killed those chips.
It wasn't one or the other but a combination of both.
The numbers I post are yes, suggestions but they are safe ones and for air cooling. The last thing I want to do is to give info to some guy and see him lose a chip or anything else.
Yes, I'm conservative but the numbers I posted will give you a solid 4600+MHz for 100% load 24/7 use and he did ask for 24/7 numbers.

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Originally Posted by DAK1640

Is that BIOS or load in windows?

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Bios settings..

Quote:

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Originally Posted by Movieman

I would respectfully disagree. I remember well when the first 45nm Yorkies came out and people treated then the same as the 65nm Kentsfields and we had a rash of dead chips on the forum.
1.4vcore with 1.45VTT killed those chips.
It wasn't one or the other but a combination of both.
The numbers I post are yes, suggestions but they are safe ones and for air cooling. The last thing I want to do is to give info to some guy and see him lose a chip or anything else.
Yes, I'm conservative but the numbers I posted will give you a solid 4600+MHz for 100% load 24/7 use and he did ask for 24/7 numbers.

Bios settings..

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Uhm I've run my i920 D0, and it was a crappy chip, with 1.45v vCore and 1.42 VTT daily use stable at 4472Mhz ( max it did... ) for like a year and a half ( on WC so temps where ~70ºC ) , that CPU is atm, stable in another build with 1.3v at 4.2Ghz on air, and it still's OK.

I'm going to stick with 1.425v for my 2600k that's the voltage for 5Ghz. Also with the new C1 state it will only achiev that under heavy load, so even safer.

But I see your conservative side of the question. I would also bet that voltagens under 1.4v would be, in any condition, safe as long as the temps are ok.

In to the nm question, I see plente of 980x runing at >1.4v, they also are 32nm and they seem ok.

2600k are a hard bone to crack, I can tell that from my own expertise.

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Originally Posted by st0ned

Uhm I've run my i920 D0, and it was a crappy chip, with 1.45v vCore and 1.42 VTT daily use stable at 4472Mhz ( max it did... ) for like a year and a half ( on WC so temps where ~70ºC ) , that CPU is atm, stable in another build with 1.3v at 4.2Ghz on air, and it still's OK.

I'm going to stick with 1.425v for my 2600k that's the voltage for 5Ghz. Also with the new C1 state it will only achiev that under heavy load, so even safer.

But I see your conservative side of the question. I would also bet that voltagens under 1.4v would be, in any condition, safe as long as the temps are ok.

In to the nm question, I see plente of 980x runing at >1.4v, they also are 32nm and they seem ok.

2600k are a hard bone to crack, I can tell that from my own expertise.

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Best of luck to you!:up:
Something that I should have added:
What we do ourselves just affects us but thats different than offerring advice to others.
When I tried to max the chip I used 1.5vcore but that was at a shot over 5GHz and MY chip and MY potential loss not someone elses.

I say 1.45v.

I have to agree with movieman.
I myself wasted hundreds of dollars degrading P4's (which were KNOWN to be very, very fragile), even running them as low as 1.625v on air. And everyone and their momma was saying that as long as you don't go higher than 1.7v (on air), you're fine. Yet just because *some* overclockers had no problems, many others had chips die or refuse to even work properly at stock or had degrading overclocks, even though the intel docs said ABSOLUTE MAXIMUM was 1.75v. So many people took absolute maximum to mean the same as max 24/7 air voltage...

And I remember how a few members on these forums (who don't post here anymore) mercilessly flamed and insulted me for being incompetent and stupid (when 1: I'm older than them, 2: I've been involved in this industry since 1994). And to make things worse, not only was I using high end air cooling (for the time) but also was not using any sort of vdroop mod.
People simply assume that just because THEY have no problems, that NO ONE ELSE will have problems either, and that's a common logical fallicy (That you usually learn about in school).

None of the people who insulted my "incompetence" offered to buy me another CPU. And it's very ironic that as the months went on, I was proven right by many other people who had these chips...others experienced degradation to various degrees as soon as they went over 1.55v.

I remember all too well what happened with the Yorkies. Dead chips, chips not stable at 3 ghz, refusing to POST in one board but posting in another...various things....and it always starts with 1 person claiming "omg it's safe", then another person trying the same settings and his chip dies...

I remember Benchzoner running yorks at 1.5vcore and 1.4 VTT 24/7 and not having them degrade or die, but that doens't mean that YOURS won't degrade or die...it's always YMMV, the instant you go out of specs.

And Movieman:
There were also people killing 980X's by treating them the same as D0 i7 920's...pumping 1.45v-1.5v into them and having them die...not many, of course..but it did happen...

Quote:

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Originally Posted by Movieman

Best of luck to you!:up:
Something that I should have added:
What we do ourselves just affects us but thats different than offerring advice to others.
When I tried to max the chip I used 1.5vcore but that was at a shot over 5GHz and MY chip and MY potential loss not someone elses.

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Thank you :D

And I do agree with you, If I didnt show it I'll now. I do agree with your voltages, 1.35v must be totaly safe. This doesn't mean you can't go higher for a daily use.

With this chips and with >1.5v you will se some degradation, I'm sure of that, but also as Sin sad, 1.45v in a good water setup that could handle temps well seems a good clock/degradation ratio in my point of view.

My chip runing with my WC settup will hit ~70ºC with 1.424v, and I do have a good WC setup. So take care of those temps.

http://img830.imageshack.us/img830/9787/5000933.th.jpg

Quote:

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And Movieman:
There were also people killing 980X's by treating them the same as D0 i7 920's...pumping 1.45v-1.5v into them and having them die...not many, of course..but it did happen..

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That might be me. From the 980X part I can't talk much because I cant afford one. Also about the chips beeing death Intel actual RMA policies are protecting us big time, hope they last...

There isn't a single number that answers your question. Each piece of silicon is unique and will respond to voltage differently, that is why VID numbers exist and are given to each CPU. It would be more accurate to ask what is the percent of over-voltage that's safe for 27/7 use, and even then, it's not going to be exactly uniform between different chips.

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Originally Posted by Falkentyne

I have to agree with movieman.
I myself wasted hundreds of dollars degrading P4's (which were KNOWN to be very, very fragile), even running them as low as 1.625v on air. And everyone and their momma was saying that as long as you don't go higher than 1.7v (on air), you're fine. Yet just because *some* overclockers had no problems, many others had chips die or refuse to even work properly at stock or had degrading overclocks, even though the intel docs said ABSOLUTE MAXIMUM was 1.75v. So many people took absolute maximum to mean the same as max 24/7 air voltage...

And I remember how a few members on these forums (who don't post here anymore) mercilessly flamed and insulted me for being incompetent and stupid (when 1: I'm older than them, 2: I've been involved in this industry since 1994). And to make things worse, not only was I using high end air cooling (for the time) but also was not using any sort of vdroop mod.
People simply assume that just because THEY have no problems, that NO ONE ELSE will have problems either, and that's a common logical fallicy (That you usually learn about in school).

None of the people who insulted my "incompetence" offered to buy me another CPU. And it's very ironic that as the months went on, I was proven right by many other people who had these chips...others experienced degradation to various degrees as soon as they went over 1.55v.

I remember all too well what happened with the Yorkies. Dead chips, chips not stable at 3 ghz, refusing to POST in one board but posting in another...various things....and it always starts with 1 person claiming "omg it's safe", then another person trying the same settings and his chip dies...

I remember Benchzoner running yorks at 1.5vcore and 1.4 VTT 24/7 and not having them degrade or die, but that doens't mean that YOURS won't degrade or die...it's always YMMV, the instant you go out of specs.

And Movieman:
There were also people killing 980X's by treating them the same as D0 i7 920's...pumping 1.45v-1.5v into them and having them die...not many, of course..but it did happen...

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I remember, it's not that long ago..
Now this is just my gut feeling with no proof BUT to me it seems like the SB chips are "tougher" than the 980-990's( and those two are different from each other) The 980's seem to be very fragile IMHO
These SB 2600K's seem to do 85-90% of max with mild voltage( under 1.4) and if you have a good boiard, good memory and "know your stuff" then you may see the "Promised Land" of 5400+:D
Now I also need to add that I'm no bencher but I do have that "I wonder what this sucker will do" inside me but I don't spend the time that many will to get that last 100MHz..
I got to 5088MHz at 1.5vcore,ran SP1m, smiled and then spend time for 4600+ for 24/7 work.

I would agree they do seem tougher then normal. I have been beating up my Sandy a lot and it still runs prime stable at 5G 1.38v and will bench at 5600 just fine. Cooling is everything and a max safe vcore can certainly be more then normal provided temps are carefully regulated.

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Originally Posted by flesheatinvirus

I would agree they do seem tougher then normal. I have been beating up my Sandy a lot and it still runs prime stable at 5G 1.38v and will bench at 5600 just fine. Cooling is everything and a max safe vcore can certainly be more then normal provided temps are carefully regulated.

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What are you using?
Keep in mind all my numbers are for air..TRUE w/113cfm Delta in open case

I am going to play it safe for now (other than a few benches) and run 4.6ish. Anything above x46 multi and Internal PLL needs to be enabled to boot with this chip, until more is learned Im not comfortable enabling that for 24/7. If I feel like abusing a chip Ill get back on the x58 board and torture my 920 some more.

Quote:

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Originally Posted by sin0822

I say 1.45v.

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how many chips have you used?

Quote:

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Originally Posted by Falkentyne

I have to agree with movieman.
I myself wasted hundreds of dollars degrading P4's (which were KNOWN to be very, very fragile), even running them as low as 1.625v on air. And everyone and their momma was saying that as long as you don't go higher than 1.7v (on air), you're fine. Yet just because *some* overclockers had no problems, many others had chips die or refuse to even work properly at stock or had degrading overclocks, even though the intel docs said ABSOLUTE MAXIMUM was 1.75v. So many people took absolute maximum to mean the same as max 24/7 air voltage...

And I remember how a few members on these forums (who don't post here anymore) mercilessly flamed and insulted me for being incompetent and stupid (when 1: I'm older than them, 2: I've been involved in this industry since 1994). And to make things worse, not only was I using high end air cooling (for the time) but also was not using any sort of vdroop mod.
People simply assume that just because THEY have no problems, that NO ONE ELSE will have problems either, and that's a common logical fallicy (That you usually learn about in school).

None of the people who insulted my "incompetence" offered to buy me another CPU. And it's very ironic that as the months went on, I was proven right by many other people who had these chips...others experienced degradation to various degrees as soon as they went over 1.55v.

I remember all too well what happened with the Yorkies. Dead chips, chips not stable at 3 ghz, refusing to POST in one board but posting in another...various things....and it always starts with 1 person claiming "omg it's safe", then another person trying the same settings and his chip dies...

I remember Benchzoner running yorks at 1.5vcore and 1.4 VTT 24/7 and not having them degrade or die, but that doens't mean that YOURS won't degrade or die...it's always YMMV, the instant you go out of specs.

And Movieman:
There were also people killing 980X's by treating them the same as D0 i7 920's...pumping 1.45v-1.5v into them and having them die...not many, of course..but it did happen...

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Actually the minority here are the overclockers you've mentioned. Any OC community's data is limited, uncontrolled, and unreliable compared to a manufacturer's lab results. Asus stated that they tested hundreds generation 2 I7 for their new motherboard lineup. I'm not even going to mention how many did Intel test with, probably tens of thousand Sandy Bridges.

I simply stated that instead of trusting any one overclocker, it is better to trust what the manufacturers said. Asus and Intel said the degradation starts around 1.55. But if you look at their recommendation, it hasn't changed much since 65nm. I sincerely disagree with people saying that just because its processing tech is even more micro-scale, it could only take less voltage. This is false, as nm scale can not be measured with .01 voltage differences.

I definitely agree with the SB being a tougher chip than the 980X. I mean, with LLC disabled, my SB was priming at 4.5 ghz (!) at auto voltages...I forgot what the BIOS setting was (I think auto gave a VID of 1.350?), but I think CPU-Z reported 1.26 under load; I know it was 1.2 something under load.

I mean, 1.2x for 4.5 ghz...
Yet the i7 980X 32nm required at least 1.4v for many people that reached 4.5 ghz on air...I guess that's logical since the 980X is simply a normal core i7 with different uncore ratio and 2 more cores on a process shrink...but that shrink did something to make the chips less durable I guess...no one had problems with 45nm i7's at 1.45, besides the temps...that's what held people back... this is still better than the tissue paper P4 days, but thank god I didn't buy the $1000 980x or 990x like I was originally going to do early this year....(to upgrade from the core 2 quad).

We'll see how things go long term. I'm at 4 ghz 1.26v, LLC off, which is good enough for 24/7... 5 ghz at 1.39v BIOS, while fully game stable (havent tried W7 SP1 yet) is just unnecessary at the moment...

I think people need to sit back and realize that we're at 5+ ghz on air now for some chips...not too long ago, 5 ghz on air was reserved for suicide shots...definitely fun times for upgrading...

The bad part is the various motherboard issues people are having...Gigabyte having cold boot loop+reinstalling devices issues, Asus having freezing problems with screeching on some boards...(haven't seen this happen on the Gigabyte side...)

Quote:

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Originally Posted by Mathemagician

I was wondering if anyone has definitive information on this topic based on hard facts from a reputable source.

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I dunno if it's reputable or definitive but readme. :shrug:

I think the 1.52v the Intel rep is saying is that the chip can USE this vcore under specification, but you had better have some high end cooling to handle that. Perhaps they realize that people are using water and sub zero a lot now, and they think that the only people who will want these documents are people who actually build and bench systems.

I personally do NOT believe that 1.52v is the MAX SAFE vcore on AIR, as the temps just skyrocket. You need chilled water or subzero....

All he said was 1.52v MAX, not max ON AIR.
So in other words, if you stay under 1.52v, your chip will still remain under warranty. Doesn't mean you can RMA it to Intel if the OC degrades...

Quote:

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Originally Posted by burebista

I dunno if it's reputable or definitive but readme. :shrug:

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Any dolt could read from a manual...

... I doubt that Dago has any more knowledge than a child would reading the manual, considering he quotes only the manual and doesn't even begin to discuss cooling, 24/7 or the fact that SB is on a smaller process.

Quote:

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Originally Posted by CedricFP

Any dolt could read from a manual...

... I doubt that Dago has any more knowledge than a child would reading the manual, considering he quotes only the manual and doesn't even begin to discuss cooling, 24/7 or the fact that SB is on a smaller process.

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What about the engineers that wrote the manual. I don't consider them dolts, as I'm sure no one else does either. They have engineered a marvel of performance/thermal efficiency that will go down as one of the best chips in Intel's history.

Intel has designed this chip to be overclocked. There are thermal limits built in, and none of us are coming close to the 90c throttle stop. They say 1.52 is safe, most are no where near that 24/7.

I for one, am overclocking on temps with this amazing platform.

And if it degrades or burns up, I'll send it back to Intel and tell them my grandmother overclocked it too far. ;-)

Quote:

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Originally Posted by burebista

I dunno if it's reputable or definitive but readme. :shrug:

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Reading through that exchange, I don't think the Intel Rep knew WTF he was talking about.

Quote:

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Originally Posted by ugotd8

What about the engineers that wrote the manual. I don't consider them dolts, as I'm sure no one else does either. They have engineered a marvel of performance/thermal efficiency that will go down as one of the best chips in Intel's history.

Intel has designed this chip to be overclocked. There are thermal limits built in, and none of us are coming close to the 90c throttle stop. They say 1.52 is safe, most are no where near that 24/7.

I for one, am overclocking on temps with this amazing platform.

And if it degrades or burns up, I'll send it back to Intel and tell them my grandmother overclocked it too far. ;-)

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I would ague that the engineers who advised those who wrote the manual did not intend the 1.52v limit to be a safe 24/7 limit. It's more likely a threshold above which CPU damage becomes significant - as in, higher than a specific margin / percentage with error taken into account.

I would say that the reps told to follow the manual, in general, are likely not knowledgeable about the implications of long term usage at particular voltages.

Considering that the person asking the rep was asking a specific question - ie, 24/7 usage, safe, etc. - the rep hardly answered his question.

Hence, any dolt can read from a manual and make incorrect inferences.

I think under 1.45V is ok

Briefly reading over the SB data sheets: http://download.intel.com/design/pro...hts/324641.pdf there is no clear answer to this question. The data sheet is also missing some very, highly useful specifications that have appeared in prior Intel data sheets (namely, absolute Vcc Max). Having read the SB specification, the VccMax reported in the VID table is the pre-determined max VID for any given processor set at the factory:

Quote:

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Each processor is programmed with a maximum valid voltage identification value (VID) that is set at manufacturing and cannot be altered. Individual maximum VID values are calibrated during manufacturing such that two processors at the same frequency may have different settings within the VID range. Note that this differs from the VID employed by the processor during a power management event (Adaptive Thermal Monitor, Enhanced Intel SpeedStep Technology, or Low Power States).

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I interpret this to mean that VccMax as specified by the VID (hard coded bits) is the max voltage attained when Turbo is engaged and power saving states change leave idle. I do not see this as the absolute max, which intel will typically specify. For example, in the i7-980X specification: http://download.intel.com/design/pro...hts/323252.pdf see section 2.10...

Quote:

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Table 2-6 specifies absolute maximum and minimum ratings, which lie outside the functional limits of the processor. Only within specified operation limits can functionality and long-term reliability be expected.
....
At conditions exceeding absolute maximum and minimum ratings, neither functionality nor l ong-term reliability can be expected. Moreover, if a device is subjected to these conditions for any length of time then, when returned to conditions within the functional operating condition limits, it will either not function or its reliability will be severely degraded.

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In other words, exceeding absolute max conditions will begin a degradation process that is not reversed if returning the CPU to the nominal factory programmed settings. The SB specification does not have such a section in it. For an i7-980X the absolute max is 1.4 V, I would take this to be probably the same region for SB (same process tech).

my conversation with an intel guy


You are now chatting with 'Brian'
Brian: Hello. Thank you for using the Intel Customer Support chat service. We are glad to be of service. How can I help you today?
we_kk_tor@hotmail.com: Hi
we_kk_tor@hotmail.com: I want to know what is the max safe voltage for sandy bridge?? no one really seems to know that, thx
Brian: Do you have the model number of one of the Intel products?
we_kk_tor@hotmail.com: you mean i5 2500k?
Brian: I am going to transfer you over to the technical department and they will continue with the process.
Brian: Please hold.
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Please wait while I transfer the chat to the best suited site operator.
You are now chatting with 'Dago'
Dago: Hello. Thank you for using the Intel Customer Support chat service. We are glad to be of service. How can I help you today?
we_kk_tor@hotmail.com: Hi
we_kk_tor@hotmail.com: I want to know what is the max safe voltage for sandy bridge?? no one really seems to know that, thx
Dago: let me check, the processor specifications, please wait
Dago: this is the processor page, now let me check your inquiry:
Dago: http://ark.intel.com/Product.aspx?id...he%2c+3.30+GHz)
we_kk_tor@hotmail.com: I cant find any volt values?
we_kk_tor@hotmail.com: the intel specs says 0.025v - 1.52v range in volt, but 1.52v just cant be safe for 24/7
we_kk_tor@hotmail.com: some says 1.38v too but I want a official max safe volt from intel, dont you know the max safe volt ?
Dago: I am checking the datasheet, please wait sir
we_kk_tor@hotmail.com: ok thx
Dago: let me confirm, are you looking the max safe voltage for the supported ram or for the processor cores?
we_kk_tor@hotmail.com: not ram, I want to know the vcore for the processor
we_kk_tor@hotmail.com: max safe
Dago: ok fine, I am checking
Dago: thanks for your patience
we_kk_tor@hotmail.com: np
Dago: please check page 78 of the following document:
Dago: http://download.intel.com/design/pro...hts/324641.pdf
we_kk_tor@hotmail.com: ok
we_kk_tor@hotmail.com: yes it is this I mean, MAX = 1.52v, but for 32nm, that just can be a safe volt for 24/7 ?? Shouldnt it be much lower ?
we_kk_tor@hotmail.com: I mean wasnt the previous 45nm max = 1.45v or something like that?
Dago: those are the specifications for this processor, the VID is (0.25) min and (1.52) max, and it is safe for 24*7
we_kk_tor@hotmail.com: ok Thx, so 1.52v for 24/7 is safe
we_kk_tor@hotmail.com: yes or no
Dago: yes
we_kk_tor@hotmail.com: Thx!
Dago: Is there something else I would be able to assist you with?
we_kk_tor@hotmail.com: no sir, this was what I want to know! thx
Dago: Thank you for using chat. We value your suggestions and would appreciate it if you would take a moment to complete our survey. The survey will appear when you click "Close'' to close the chat window. Have a nice day.

I'm keeping my 2600K at it's sweetspot. Which is 4.5 at 1.28Vcore, for 4.6 I need 1.33ish and temps go up pretty steep (all on high end watercooling).

For benching preps I use 1.5Vcore for 5.2. It's 3D stable then...

I honestly feel daily usage won't rapidly degrade the chip (except folding 24/7), but all this uber stability testing does more harm then good...

Subscribed.... Interesting read

Quote:

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Originally Posted by Leeghoofd

I'm keeping my 2600K at it's sweetspot. Which is 4.5 at 1.28Vcore, for 4.6 I need 1.33ish and temps go up pretty steep (all on high end watercooling).

For benching preps I use 1.5Vcore for 5.2. It's 3D stable then...

I honestly feel daily usage won't rapidly degrade the chip (except folding 24/7), but all this uber stability testing does more harm then good...

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I just got my SB, and still testing, but I've observed a jump/bump in vCore around 4.5GHz too. I had a few short 10-min Prime-runs, and these may need minor adjustments, but I got these so far: EDIT(putting in exact vCore)
4.5GHz = 1.272v
4.6GHz = 1.296v
4.7GHz = 1.336v

4.5 to 4.6 needs 0.024v increase, while 4.6 to 4.7 needs 0.040v, that's a bump/jump. Next jump will probably get steeper, maybe 0.08v, but I didn't have time to test 4.8Ghz yet.

Generally, vCore requirement (and the heat-signature too actually) may vary depending on you CPU-Batch#, but 24/7 OC is not about pushing it to the limits and edges. Even if you can get away with "safe"-voltages, you would usually need excessive vCore (and other voltages too) to get there.

24/7 OC is all about the sweet-spot, and it's a good idea to settle down when the vCore makes a sudden jump/bump. But it's always fun trying to push for benching testing tho.

Quote:

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Originally Posted by Leeghoofd

I'm keeping my 2600K at it's sweetspot. Which is 4.5 at 1.28Vcore, for 4.6 I need 1.33ish and temps go up pretty steep (all on high end watercooling).

For benching preps I use 1.5Vcore for 5.2. It's 3D stable then...

I honestly feel daily usage won't rapidly degrade the chip (except folding 24/7), but all this uber stability testing does more harm then good...

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Lee,
You were right dead on back during the core 2 days, when you talked about degradation. The Yorkies would experience a little bit of degradation even at lower voltages (like 1.36), sometimes as much as 0.04, and then would stabilize. Which is exactly what you said.
But repeated abuse and linpack and small FFT stress testing only helped make them degrade more, and faster...

I feel that all this 12 hour linpack/prime testing at high voltages does nothing but help degrade the chips...they're going through abuse they really werent meant to withstand ...

^^^ agree with that

Id say 1.375, or thats what ive heard so far.

My personal opinion is 1.38v for Top Air cooling and 1.42v for top water cooling. Anything over 1.45v will degrade the chip over time. Running 5 GHz @ 1.5v because you can, doesn't mean you should.

Thank you all for sharing. This is actually a practical matter for me rather than a theoretical one. I am not a gamer. I overclock work PCs because much of the work that I do is very CPU-intensive. Every MHz that I can squeeze out of a box translates to time saved, and over the service life of these PCs this time saved can be worth a good deal more than $330 for a new chip. (Roughly speaking, a 10% gain in CPU speed turns a 10 hr procedure into a 9 hr procedure. Two such procedures a week adds up to 100 hrs/year/box.) After that, they become email/web/goofing off family PCs and can be clocked conservatively. The effective service life of these PCs tends to be 1-2 years. So, what I'm really trying to do is get a good sense of the relationship between vcore+temp and rate of degradation, and find the sweet spot along that curve for my application. This process has been complicated because it's just been far too easy to find opinions (some of which are highly valuable when based on the extensive experience many of you have) and far too difficult to find hard facts in this area. Hopefully this will help frame the discussion a bit more effectively. Thanks again for your input.

It was 1.4V for both other 32nm chips (Westmere: Gulftown and Clarkdale). I'd also stick to that. There were cases of people killing SB at 1.6V in a couple of days...
And temperature wise, I'd recommend staying below 70C at all times.
I obviously don't know for sure, but seems pretty accurate to me.

wow "some" of you guys are just blurting out numbers...

sheeesh

an idiot/kid/idiot(again) would just stick to 1.45v...then prime95 for 1-4 weeks..and confirm your fhucking recommendation and kill their chip.....or it will survive...or it will degrade.

1.36v 5Ghz for me maybe higher when all my new hardware is here!

nm and voltage? i just dont understand..

Pentium® 4 Processor Extreme Edition supporting HT Technology 3.73 GHz
90nm
VID Voltage Range: 1.200V-1.400V

Intel® Pentium® Processor Extreme Edition 955
65nm
VID Voltage Range: 1.200V-1.3375V

Intel® Core™2 Quad Processor Q9650
45nm
VID Voltage Range: 0.8500V-1.3625V

Intel® Core™2 Duo Processor E4300
65nm
VID Voltage Range: 0.8500V-1.5V

This is what Im doing for voltage:
1.4v for 24/7 and stick to 100 bclk
1.52v for 3d and CPU intensive benches, bclk oc ok
1.62v for 2d, PI and pifast only, bclk oc ok

Also, there is no need for excessive stress testing, that is just asking for trouble with these chips. Run LinX or similar for an hour, chances are you will be fine with that.

I have a 5.7+ Ghz chip and no degradation at all thus far with the above.

intel says 1.52v is safe for 24/7, I dont understand why people claims other voltages then?

Where does Intel say that?

here, and I have already posted that:

my conversation with an intel guy


You are now chatting with 'Brian'
Brian: Hello. Thank you for using the Intel Customer Support chat service. We are glad to be of service. How can I help you today?
we_kk_tor@hotmail.com: Hi
we_kk_tor@hotmail.com: I want to know what is the max safe voltage for sandy bridge?? no one really seems to know that, thx
Brian: Do you have the model number of one of the Intel products?
we_kk_tor@hotmail.com: you mean i5 2500k?
Brian: I am going to transfer you over to the technical department and they will continue with the process.
Brian: Please hold.
we_kk_tor@hotmail.com: ok thx
Please wait while I transfer the chat to the best suited site operator.
You are now chatting with 'Dago'
Dago: Hello. Thank you for using the Intel Customer Support chat service. We are glad to be of service. How can I help you today?
we_kk_tor@hotmail.com: Hi
we_kk_tor@hotmail.com: I want to know what is the max safe voltage for sandy bridge?? no one really seems to know that, thx
Dago: let me check, the processor specifications, please wait
Dago: this is the processor page, now let me check your inquiry:
Dago: http://ark.intel.com/Product.aspx?id...he%2c+3.30+GHz)
we_kk_tor@hotmail.com: I cant find any volt values?
we_kk_tor@hotmail.com: the intel specs says 0.025v - 1.52v range in volt, but 1.52v just cant be safe for 24/7
we_kk_tor@hotmail.com: some says 1.38v too but I want a official max safe volt from intel, dont you know the max safe volt ?
Dago: I am checking the datasheet, please wait sir
we_kk_tor@hotmail.com: ok thx
Dago: let me confirm, are you looking the max safe voltage for the supported ram or for the processor cores?
we_kk_tor@hotmail.com: not ram, I want to know the vcore for the processor
we_kk_tor@hotmail.com: max safe
Dago: ok fine, I am checking
Dago: thanks for your patience
we_kk_tor@hotmail.com: np
Dago: please check page 78 of the following document:
Dago: http://download.intel.com/design/pro...hts/324641.pdf
we_kk_tor@hotmail.com: ok
we_kk_tor@hotmail.com: yes it is this I mean, MAX = 1.52v, but for 32nm, that just can be a safe volt for 24/7 ?? Shouldnt it be much lower ?
we_kk_tor@hotmail.com: I mean wasnt the previous 45nm max = 1.45v or something like that?
Dago: those are the specifications for this processor, the VID is (0.25) min and (1.52) max, and it is safe for 24*7
we_kk_tor@hotmail.com: ok Thx, so 1.52v for 24/7 is safe
we_kk_tor@hotmail.com: yes or no
Dago: yes
we_kk_tor@hotmail.com: Thx!
Dago: Is there something else I would be able to assist you with?
we_kk_tor@hotmail.com: no sir, this was what I want to know! thx
Dago: Thank you for using chat. We value your suggestions and would appreciate it if you would take a moment to complete our survey. The survey will appear when you click "Close'' to close the chat window. Have a nice day.

all cpu's diffirent than others. a cpu can select any vid from a vid range for thermal properties. what about if a cpu select 1.52v for run? then you can run 1.52v 7/24 at stock clocks. overclock is realy diffirent bussnies but i dont think 1.52 volt going damage any cpu component.


and intel live support no idea what we are talking about..

Allan: Hello. Thank you for using the Intel Customer Support chat service. We are glad to be of service. How can I help you today?

aytacaksel@gmail.com: hi

aytacaksel@gmail.com: i have a question

Allan: yes

aytacaksel@gmail.com: i know maybe alot ppl asking for same thing but i wanna ask again

aytacaksel@gmail.com: sandy bridge max vcore :P

aytacaksel@gmail.com: is it realy safe running 1.52 volt 7/24 if cooling isnt problem

Allan: what is your processor model?

aytacaksel@gmail.com: i5 2500k

Allan: Please wait for 2 minutes and I will check your concern. Thank you.

aytacaksel@gmail.com: thank you

Allan: I remind you that Vcore information may not be available as this can be used for overclocking...

Allan: please hold

aytacaksel@gmail.com: yea i realy dont care my cpu can burn but why i buyed 2500k? :P

aytacaksel@gmail.com: just wanna learn my limits

Allan: actually, the information is not available...

Allan: Intel does not provide that information

aytacaksel@gmail.com: oh

aytacaksel@gmail.com: okay thank you then

Allan: you're welcome.

Allan: Thank you for using chat. We value your suggestions and would appreciate it if you would take a moment to complete our survey. The survey will appear when you click "Close'' to close the chat window. Have a nice day.

Chat InformationChat session has been terminated by the site operator.

Uh yeah I dont think Im going to risk my golden chip on a conversation with some guy that doesnt sound like he knows what he is talking about..

The question is... will you cry if the chip dies? If yes, then run 1.35v without internal PLL increase. If not, then run 1.45 with PLL increase... 1.5 is a little silly for 24/7 as there are multiple cases of this killing/degrading chips in just days. 1.45 is not known yet and might be safe. Not much is known about the increase internal PLL checkbox we are all enabling...

Also guys, if you want even safer and greener(lol) way, use offset setting. Even if your load is 1.4, it will automatically scale down to below 1.0 at rest.

Quote:

---

Originally Posted by Eldonko

Also, there is no need for excessive stress testing, that is just asking for trouble with these chips. Run LinX or similar for an hour, chances are you will be fine with that.

---

Would Folding@Home 24/7 be considered a form of "stress testing"? I find it pointless to overclock a CPU to 4.8+ only to let it sit idle 99% of the time.

Quote:

---

Originally Posted by Falkentyne

Lee,
You were right dead on back during the core 2 days, when you talked about degradation. The Yorkies would experience a little bit of degradation even at lower voltages (like 1.36), sometimes as much as 0.04, and then would stabilize. Which is exactly what you said.
But repeated abuse and linpack and small FFT stress testing only helped make them degrade more, and faster...

I feel that all this 12 hour linpack/prime testing at high voltages does nothing but help degrade the chips...they're going through abuse they really werent meant to withstand ...

---

:up::up::up:
:soap:
I sometimes wonder where common sense has gone.
I would like all of you guys to stop and just think about what your subjecting your chips to when you run these linpack and prime 95 apps for hours on end.
Now you guys know I do DC work and it loads the cpu's to an indicated 100% load and my machines run at 100% load 24/7 for years on end.
All on good air cooling and the maximum temp I will allow a machine to run at is 65C.
The difference in loaded temps between the DC apps and these bench apps is HUGE. These apps are not real world and you are subjecting them to stress that they would never normally see so why do this?
You pay hunndreds of dollars for your cpu and then set out to prove it will do X with these apps and then a few months later wonder why your cpu is degraded?
Run SP32m, in most cases if it will run that then it is stable for almost anything you will use it for in daily life.
End of rant.

+1, well said movieman.

I used 5-10 minutes of prime blend custom to get the general ballpark. Then I use SPECapc for Lightwave and if I can get thru that, I'm stable. Killing my chip trying to join an e-peen club is not my idea of fun.

my chip like 1.42v for 4.8Ghz and 1.48v for 5Ghz , anything under my system crash , but i saw some nice chip that need only 1.27 for 4.7ghz

I think 1.5v is the max safety Vcore

Quote:

---

Originally Posted by Movieman

:up::up::up:
:soap:
I sometimes wonder where common sense has gone.
I would like all of you guys to stop and just think about what your subjecting your chips to when you run these linpack and prime 95 apps for hours on end.
Now you guys know I do DC work and it loads the cpu's to an indicated 100% load and my machines run at 100% load 24/7 for years on end.
All on good air cooling and the maximum temp I will allow a machine to run at is 65C.
The difference in loaded temps between the DC apps and these bench apps is HUGE. These apps are not real world and you are subjecting them to stress that they would never normally see so why do this?
You pay hunndreds of dollars for your cpu and then set out to prove it will do X with these apps and then a few months later wonder why your cpu is degraded?
Run SP32m, in most cases if it will run that then it is stable for almost anything you will use it for in daily life.
End of rant.

---

You see, some of us needs to push these CPUs to the limits and distinguish it from the rest. Now it's not possible to put these CPUs under LN2 and get a 7GHz+ SuperPi1M-shot. Everybody is going to get stuck around 5.7Ghz +/- anyways.

This seams to be creating some kind of fenestrations, and then some keep LinXing and Priming at the limit of these CPUs to distinguish it from the rest, but you are right (gain) that's not a good idea at all.

Listen for a minute.
We're all different with different wants and uses.
All I want to get across is use some good old fashioned common sense when you test your chips as the thing I hate to see most is some 17 year old kid reading these threads then going out and blowing up parts that he can't afford to replace.
I run at 4634. Can I get more? Yes.
Ran 32m on this at 5088MHz on air and I mean real 70F air not minus 15F on my back porch.:D
BUT to me what I want is a solid running system at a speed that my mind says is a good long term setting with temps I'm comfortable with and I think I have that.

In my testing on the SPECapc lightwave render tests my chip can do:

451 seconds @ 4.8GHz max temp 71c
431 seconds @ 5.0GHz max temp 76c

5 percent gain for 5c ? I don't think it's worth it. 71c should get better this weekend tho, going under water.

This magical 5GHz number is making usually rational people insane.

Quote:

---

Originally Posted by ugotd8

In my testing on the SPECapc lightwave render tests my chip can do:

451 seconds @ 4.8GHz max temp 71c
431 seconds @ 5.0GHz max temp 76c

5 percent gain for 5c ? I don't think it's worth it. 71c should get better this weekend tho, going under water.

This magical 5GHz number is making usually rational people insane.

---

Yes, and it's not ending there.
The guys know that in theory the 2600K's have a max 57 multi and they want that speed so you will see people killing these to try to get there.
Then who will be the first to get to 6GHz..
That's 57x105.26..
See what I mean?
It never ends..:rofl:

Some kind of stability testing is needed for a 24/7 machine. It's not going anywhere.
The amount and methods are subjective, however. Nobody is forcing anyone to run Prime or LinX for days. Everyone has their own measure of stability, it's them who is picking methods, and it's them who is responsible for the consequences.

Absolutely. FAH is still going to stress all cores 24/7 but it is going to be a hell of a lot cooler than running stress tests that nothing comes close to replicating in the real world. Plus there is a reason to do it.

Quote:

---

Originally Posted by zoob

Would Folding@Home 24/7 be considered a form of "stress testing"? I find it pointless to overclock a CPU to 4.8+ only to let it sit idle 99% of the time.

---

i gave up doing long term stress testing on these chips because i did see voltage degradation at an early stage at 5.2ghz and 1.5v then upto 1.55v, but with LLC level2 so 1.53v to 1.58v, its pretty terrible, but that is what happened over time, now my chip gets to hot to OC on air, and on water or cold air the CPu won't do 5.2ghz, because it has a 20c cold bug, took me weeks to figure it out, but it drove me nuts.

Hondacity 2 chips over 2 months at least. Both D1 stepping and i did run into voltage degradation as well as much different OCes, and these chips were heavily used before i got them.

Do you suspect that it could be related to D1 and perhaps D2 is better?

I will always make sure I am prime or linx stable with my 24/7 settings, as I dont like BSODs/corrupt OSes, but again stability testing is one of those to each his own. Also, some run prime 24/7 to search for prime numbers, just like others fold 24/7. And, I can do 32m spi at 4.9 ghz on my i950, but it is not close to stable.

That being said, I do agree that many of us run prime/linx at almost benching mhz/vcore and that may contribute to or cause degradation, but just like benching at crazy vcore, the user just needs to be aware and accept the consequences of having fun. And for some of us, myself included, it is fun seeing what you can get stable, just like it fun seeing what you can get max spi 1m, sp32m, SS, etc.

Quote:

---

Originally Posted by Hondacity

wow "some" of you guys are just blurting out numbers...

sheeesh

an idiot/kid/idiot(again) would just stick to 1.45v...then prime95 for 1-4 weeks..and confirm your fhucking recommendation and kill their chip.....or it will survive...or it will degrade.

---

Yup, an awful lot of that going on here.

why are so many people biyatching about the fact that because they don't have access to LN2, they can't reach higer? Asus already stated that with SBs, it is actually worse to go subzero. If you can't go higer with decent temp, you won't get anymore from LN2. So stop biyatching.

Quote:

---

Originally Posted by flesheatinvirus

Yup, an awful lot of that going on here.

---

Hey you guys take it easy. No reason to use offensive language. People have different preferences and different ideas about how they want to test their setup. Addressing them as "idiot/kid/idiot" is idiotic.

I always take it easy. Thank You for caring though.

Personally it will be 1.3V or over 65 degrees Linx/Prime95 load, which ever comes first.

But people need to be responsible for what they do, instead of saying stuff (like was posted on hardforums) that you HAVE to prime to make sure your cpu is stable. I had to troll away in that thread, PROVING that you do NOT need to small FFT, showing that my Rybka Chess engine is quite enough for me.

Now, Prime Blend *IS* a useful test. The temps don't get anywhere NEAR the small fft test, and are about a couple of C higher than Rybka, and is a great test to show RAM stability as well. If you can NOT do prime blend, then you are NOT stable at all, and you also risk OS corruption. (I had prime blend give me an error on ALL cores after one test (didn't even get to one pass), when overclocking my RAM (might have needed 1.65v) and I bluescreened right when a round of the game Crossfire ended (yes, the game). At the very least, maybe people can back off the small FFT abuse a bit and try blend to see if their systems will pass that. If they will, then try some gaming or folding and see how it holds up. You don't need to take your system to the edge to show you're stable.

And if your RAM isn't stable, Prime Blend will usually CRASH within the first few minutes. So if you can pass even ONE full pass of blend, your OS won't get wiped due to RAM errors. No need to let it loop overnight...

When I was having problems at *STOCK* on my other system (freezes in games even at stock), I ran prime blend and was getting crashes in about 30 seconds. Small FFT ran forever...(a reseat of the 12v 4 pin fixed that).

About LinX:
Lin X is NOT even supposed to be used as a stability test. It's an internal Intel app designed for binning CPU's and QA testing them. When Lin X came out, people praised it for giving you the option of running it for 30 minutes to test stability, instead of having to run Prime for 12 hours to do the same thing, so they would put less stress on the chips. But the temps got oh-so-much hotter than small fft's. Now, people are running LinX for hours...

Absolutely correct and well said IMO.

Quote:

---

Originally Posted by Falkentyne

But people need to be responsible for what they do, instead of saying stuff (like was posted on hardforums) that you HAVE to prime to make sure your cpu is stable. I had to troll away in that thread, PROVING that you do NOT need to small FFT, showing that my Rybka Chess engine is quite enough for me.

Now, Prime Blend *IS* a useful test. The temps don't get anywhere NEAR the small fft test, and are about a couple of C higher than Rybka, and is a great test to show RAM stability as well. If you can NOT do prime blend, then you are NOT stable at all, and you also risk OS corruption. (I had prime blend give me an error on ALL cores after one test (didn't even get to one pass), when overclocking my RAM (might have needed 1.65v) and I bluescreened right when a round of the game Crossfire ended (yes, the game). At the very least, maybe people can back off the small FFT abuse a bit and try blend to see if their systems will pass that. If they will, then try some gaming or folding and see how it holds up. You don't need to take your system to the edge to show you're stable.

And if your RAM isn't stable, Prime Blend will usually CRASH within the first few minutes. So if you can pass even ONE full pass of blend, your OS won't get wiped due to RAM errors. No need to let it loop overnight...

When I was having problems at *STOCK* on my other system (freezes in games even at stock), I ran prime blend and was getting crashes in about 30 seconds. Small FFT ran forever...(a reseat of the 12v 4 pin fixed that).

About LinX:
Lin X is NOT even supposed to be used as a stability test. It's an internal Intel app designed for binning CPU's and QA testing them. When Lin X came out, people praised it for giving you the option of running it for 30 minutes to test stability, instead of having to run Prime for 12 hours to do the same thing, so they would put less stress on the chips. But the temps got oh-so-much hotter than small fft's. Now, people are running LinX for hours...

---

Sorry to bump this old thread guys, but this is just great post :up::clap: