Core i7/X58 Overclocking Thread

[dejanh]

dejanh, I have always been told that an overclock can't really be considered stable unless you can run prime (small FFTs) for 12 hours+ Can you??

Also, just out of interest what speed are you running your RAM @ now for that 4.2GHz clock?

Just sitting here waiting for the courier to turn up with i7 940 before I can see if 4.2GHz HT enabled if possible.

With regards to temps... don't be too sure about getting 4.3-4.6GHz with better cooling... I have a quad rad & GTZ block on a dedicated loop. My temps never exceeded 72c on my i7 920, however, I could not get past 4.0GHz prime (small FFTs) stable. 4.0GHz or below with HT & Turbo enabled is solid as a rock for me. But I want more!

Well, I've been overclocking for 12 years now and I can only speak from my experience but Prime (in any form) is not always an indicator of stability. On my old AMD system with a 5000+ BE I could Prime all day long at 3.2GHz, but I know for a fact that it was not 100% stable, for example. That's why I am not longer a big speaker for Prime (or for that matter any one stress tool). You will also notice huge differences when running Prime 32-bit and Prime 64-bit, so what then? Do you say that unless you are full-day stable in both Primes under all three options for running it you are not absolutely stable? Or better yet, blend tests say they test RAM, but I am certain that they do not test 6GB of ram, so what then?

Anyway, I think you get my point. I ran Prime for about 2 hours, temps were stable, everything was stable. For me that is good enough. Indeed, in most cases I will not run Prime for more than 30 minutes before I declare an OC stable. This has never failed me in the past and I doubt it will be any different now. I will also almost bet you that if you leave Prime running just long enough with a hefty OC, your system will crash. How long that "just long enough" may be is subjective and dependent on your OC. It may be hours, may be days, maybe a week.

Now, I am running my ram at 1603MHz, 7-8-7-20-1T timings, 1.35000V QPI/DRAM, 1.65681V DRAM.

I have so far gone through tree different i7 940s. The first clocked better at lower volts than the second but it was a hot chip, so it maxed out at 4GHz. Second was just bad as it was never fully stable at 4GHz even if you up the voltages to 1.46V (as high as I would go on air). Finally, this third chip now is a bit hotter than #2, but better than #1 and #2 in both volts and clocks.

[ReverendMaynard]

Well, I've been overclocking for 12 years now and I can only speak from my experience but Prime (in any form) is not always an indicator of stability. On my old AMD system with a 5000+ BE I could Prime all day long at 3.2GHz, but I know for a fact that it was not 100% stable, for example. That's why I am not longer a big speaker for Prime (or for that matter any one stress tool). You will also notice huge differences when running Prime 32-bit and Prime 64-bit, so what then? Do you say that unless you are full-day stable in both Primes under all three options for running it you are not absolutely stable? Or better yet, blend tests say they test RAM, but I am certain that they do not test 6GB of ram, so what then?

Anyway, I think you get my point. I ran Prime for about 2 hours, temps were stable, everything was stable. For me that is good enough. Indeed, in most cases I will not run Prime for more than 30 minutes before I declare an OC stable. This has never failed me in the past and I doubt it will be any different now. I will also almost bet you that if you leave Prime running just long enough with a hefty OC, your system will crash. How long that "just long enough" may be is subjective and dependent on your OC. It may be hours, may be days, maybe a week.

Now, I am running my ram at 1603MHz, 7-8-7-20-1T timings, 1.35000V QPI/DRAM, 1.65681V DRAM.

I have so far gone through tree different i7 940s. The first clocked better at lower volts than the second but it was a hot chip, so it maxed out at 4GHz. Second was just bad as it was never fully stable at 4GHz even if you up the voltages to 1.46V (as high as I would go on air). Finally, this third chip now is a bit hotter than #2, but better than #1 and #2 in both volts and clocks.

Cheers to that dejanh. Also...kudos for using Arena Chess...I ran it for 2 hours last week and crept up into the 80's just like linpack did. Realworld stability FTMFW.

[highoctane]

Or better yet, blend tests say they test RAM, but I am certain that they do not test 6GB of ram, so what then?

Well prime 64bit will only allocate like 1.6gb per session from what I can tell. To get around that I just start multiple prime sessions with 2 threads each and run custom on the last one to use up whatever ram is left as well as turn pagefile off, seems to do decent at allocating most the memory to prime.

For me personally, if it doesn't go at least prime for more than 24hrs I don't even bother with other testing till I get a minimum of 24hrs prime stable but I agree prime does not mean 100% under every load, a great starting point though.

I'm still priming my i7, not the killer clock of others but good enough for 24/7:

[The-Fox]

I do all three anyway.

I'd still love to see a prime95 stable 4.2GHz rig with HT enaled. Blend or small FFT's not fussed really, just 12 hours+ as proof it can be done on water or air.

It is doable on Water, on air it is very hard and you need a CPU which works at a very low voltage and even then, you will most likely to work at very high temps (80+) which are not healthy.

I am pretty sure of it and I don't think there is a need to run 12Hr Prime, 30 minute run with Linpack is enough, it the ultimate turtore test

[bmilos]

Anyone running a vapochill ls on their i7 have any temps to share? Im thinking about picking one up and curious at its 24/7 performance..

thanks.

[dejanh]

Cheers to that dejanh. Also...kudos for using Arena Chess...I ran it for 2 hours last week and crept up into the 80's just like linpack did. Realworld stability FTMFW.

Indeed. Arena is nice. Very nice real-world test

[Lukee]

I have a question. I have an "A" chip. I can buy a "B" guaranteed for like 280 or so. Should I do it? My chip requires insane qpi/vtt for more than 200 bclk.

right now I am running 200 x 21 turbo off with 1.376 in CPU-Z. I got my chip with the 25% Live discount so by selling it at 250 or even 225 I wont be really losing out on anything.. what do you guys think? i wanted to try to run 210 or 215 bclk so as to OC my memory a bit.

Thanks in advance.

[roller11]

Are the B chips suppose to be better?

[ReverendMaynard]

I have a question. I have an "A" chip. I can buy a "B" guaranteed for like 280 or so. Should I do it? My chip requires insane qpi/vtt for more than 200 bclk.

right now I am running 200 x 21 turbo off with 1.376 in CPU-Z. I got my chip with the 25% Live discount so by selling it at 250 or even 225 I wont be really losing out on anything.. what do you guys think? i wanted to try to run 210 or 215 bclk so as to OC my memory a bit.

Thanks in advance.

If you're not losing out on anything...go for it. Mine has done well, but I wouldn't put a stamp on the B's as golden quite yet. Need more data

[YukonTrooper]

@ bmilos

got the same case as me, looks good, here is a few shots of mine:

@ GNU

Check out the pics if you'd like to, they are cell phone pics, but oh well, you can still see the system.

Mine consists of thermaltake pump and reservoir, Koolance 120.1 radiator, and Swiftech Apogee GTZ water block.

Aren't you getting insane temps with that loop and clock? Especially in Florida! Unless, of course, you have AC. Some folks seem to be complaining about dual 120mm rads on just the CPU loop, yet you're on a single 120mm at 4.2GHz/1.4v?!

[dejanh]

I have a question. I have an "A" chip. I can buy a "B" guaranteed for like 280 or so. Should I do it? My chip requires insane qpi/vtt for more than 200 bclk.

right now I am running 200 x 21 turbo off with 1.376 in CPU-Z. I got my chip with the 25% Live discount so by selling it at 250 or even 225 I wont be really losing out on anything.. what do you guys think? i wanted to try to run 210 or 215 bclk so as to OC my memory a bit.

Thanks in advance.

That is not a very high voltage. "B" will not guarantee you lower voltages. Indeed, one of the lowest voltage chips that was posted here was an "A" chip...

I would not be too quick to change it like that. I have done things like that in the past and have definitely gotten screwed more than once.

[Truckchase!]

Well, I've been overclocking for 12 years now and I can only speak from my experience but Prime (in any form) is not always an indicator of stability. On my old AMD system with a 5000+ BE I could Prime all day long at 3.2GHz, but I know for a fact that it was not 100% stable, for example. That's why I am not longer a big speaker for Prime (or for that matter any one stress tool). You will also notice huge differences when running Prime 32-bit and Prime 64-bit, so what then? Do you say that unless you are full-day stable in both Primes under all three options for running it you are not absolutely stable? Or better yet, blend tests say they test RAM, but I am certain that they do not test 6GB of ram, so what then?

Anyway, I think you get my point. I ran Prime for about 2 hours, temps were stable, everything was stable. For me that is good enough. Indeed, in most cases I will not run Prime for more than 30 minutes before I declare an OC stable. This has never failed me in the past and I doubt it will be any different now. I will also almost bet you that if you leave Prime running just long enough with a hefty OC, your system will crash. How long that "just long enough" may be is subjective and dependent on your OC. It may be hours, may be days, maybe a week.

I must respectfully disagree; I really appreciate the work you've put into this thread and it's enlightened me quite a bit, but I beg to differ on this one. I think it's important on boards like this to have a certain set of standards regarding when an overclock is considered relatively stable for the purposes of spreading correct information regarding expectations. While I completely agree with your assessment that 24/7 for a month doesn't necessarily equate to stability, I also believe it's important to use the most scientific means at our disposal to render judgment on what may or may not be considered stable. I also agree that having alot of experience overclocking can lead to having a good "gut feel" of stability, but one must remember that alot of folks in this forum (albeit not as much as other forums) are newer and looking for advice. Developing that "gut feel" takes years of practice.

That being said, I would like to recommend to anyone seeking advice that anything in the area of 12 hrs of prime or 6 hrs of LinX goes a long way to "prove" stability.

Comments welcome, but I don't want to hijack this thread; so try not to pay too much attention to me.

On that note, I just got my P6T deluxe/920/6GB OCZ 1600 Plat. Seems to be a great chip, I could hit 3.6Ghz on water at just above stock volts. I'm still learning this platform and will post results when I get anything substantial.

Thanks!

[avrionis]

Finally got my water block (re: GTZ), I had a Vendetta 2 HS with idle temps that seem to match the GTZ.

I am running at 3.8G with 1.29375V cpu, 1.66 VDIMM, 1.375 QPI on a Asus P6T. My temps at idle is 38C and on load (folding with 90% cpu usuage) 60C. Do those temps sound proper. I have a open case for now. Cannot understand it matchs my temps I had with the OCZ Heatsink Vendetta 2. Also, tried to see what my idle temps at stock settings, it still is around 30C which seems high since my ambient in my basement is about 24C.

I have always been a D-tek WB person, but could not what for the backplate. I have been running with the same loop & case except for the WB which I was using the D-Tek Fusion, my idle temps of my QX6850 at 3.8G with about 1.47V was at 26C.

Tried switching/re-installing the WB a few times, redone my fluid, I have tried all sorts but still have those temps. I hope it is not due to the GTZ WB.

Any help is appreciated.

P.S> It is a cpu only loop with a thermo PA120.3 rad with 6 push/pull 120CFM fans.

[YukonTrooper]

Same load temps as your Vendetta 2? What were you using to hold your Vendetta 2 in place?

[avrionis]

I fixed up the Thermalright LGA1366 BOLT-THRU Kit to hold my Vendetta.

[YukonTrooper]

Interesting. We'll talk about this in PM's. Don't want to derail the thread.

[Leeghoofd]

Idle temps are mostly the same between a high performance cooler and a good watercooling setup, though there should be some difference in load here.. and thermochill rads are designed for high performance with low rpm fans, think they hardly benefit from 120CFM fans

I have the Swiftech Ultima kit here for a review will hook it up on friday... tubing and pump can mean a big difference here... and folding even at 100% has usually lower load temps then small FFT prime... try a prime test and see how the temps evolve then... I will check this all out in the review compared with a TRUE, bigger rad, 1/2 tubing etc..

[freshy]

It is doable on Water, on air it is very hard and you need a CPU which works at a very low voltage and even then, you will most likely to work at very high temps (80+) which are not healthy.

I am pretty sure of it and I don't think there is a need to run 12Hr Prime, 30 minute run with Linpack is enough, it the ultimate turtore test

i got an error after 8 1/2 hours in prime @4.2ghz but it just needs to much voltage over 1.5v with turbo on and ht on

so im just on 4.1ghz 24/7, for now over 19 hours prime stable small ftt and blend, but ive gotten errors in prime even after 19 hours too

[JWMc]

I'm having a lot of fun overclocking this 920 on a UD5 on the table here:

http://www.xtremesystems.org/forums/...postcount=1273

Sorry I don't have any screenshots yet, only been working on the chip for a short time.

[Raadster]

P.S> It is a cpu only loop with a thermo PA120.3 rad with 6 push/pull 120CFM fans.

You have reached your lowest temps for sure, aside from lapping your cpu you are at the peak.

Your rad could take a gpu in that loop as well and the fact you have a whopping 6 120cfm fans on that rad definitely proves your done temp wise.

Are you deaf yet?

[speckled10]

Cheers to that dejanh. Also...kudos for using Arena Chess...I ran it for 2 hours last week and crept up into the 80's just like linpack did. Realworld stability FTMFW.

I for one am pretty sick of this Prime95 holy grail .. OK so I cannot get more than a couple of hours @ 4Ghz of Prime to save my life with reasonable voltage ..

So what ???

I have my 'game stable' setup which involves the following:

- At least 5 mins of OCCT
- At least 5 mins of Arena
- At least 5 loops of Cinebench
- At least 5 loops of wPrime
- At least 5 mins of Everest Stability
- At least 5 loops of SuperPI

- At least 2 hours of Crysis/Assassins/Far Cry 2/POP etc ...

This may sound pretty lame for an OC test .. but I have pretty much proven if it passes these tests.. it will play games for hours .. and encode DVD's etc. . and thats the main reason I bought the machine ..

Besides I've also heard enough stories of machines that are prime stable for 15 hours then fall over idling or playing simple games ..

I know which machine I'd rather have .. game stable not prime stable

[The-Fox]

P.S> It is a cpu only loop with a thermo PA120.3 rad with 6 push/pull 120CFM fans.

Who in the world uses termochill with 6 120cfm fans ?!?!
That is what HW Labs GTX rads are for.
The high fin count benefit from high CFM which means 120mm fans @ more than 1500rpm.
Anyway, using a small fin count rad like the termochill along with 6 fans of very high CFM is a complete waste of CFM.

Regardless of this, you are probably deaf by now

P.S.
Did you mount the block at the correct orientation as described by the manual ?
It needs to be installed in an exact orientation as the block is bowed.
Moreover, make sure you put a medium size drop of thermal grease, put the block on and give it a little twist, to the left and to the right.
Finally, make sure to use the highest pressure possible (due to the bow in the block), meaning you should close the screws all the way down.

The GTZ block is a very well one, I am getting about 70c top at 4.2Ghz with HT on and Vcore @ 1.5v with the case close.
My cooling loop is in my sig.

Your temps are high considering the huge amount of air going through your rad.

[NBF]

Idle temps are mostly the same between a high performance cooler and a good watercooling setup, though there should be some difference in load here.. and thermochill rads are designed for high performance with low rpm fans, think they hardly benefit from 120CFM fans

I have the Swiftech Ultima kit here for a review will hook it up on friday... tubing and pump can mean a big difference here... and folding even at 100% has usually lower load temps then small FFT prime... try a prime test and see how the temps evolve then... I will check this all out in the review compared with a TRUE, bigger rad, 1/2 tubing etc..

Interesting review Leeghoofd, please share when its done.

I would love to see how the Swiftech Ultima goes against TRUE on i7, it seems like a very wise buy regarding price/performance.

[Lukee]

That is not a very high voltage. "B" will not guarantee you lower voltages. Indeed, one of the lowest voltage chips that was posted here was an "A" chip...

I would not be too quick to change it like that. I have done things like that in the past and have definitely gotten screwed more than once.

What I'm really looking for is to go past 200 Bclk without having to use an insane amount of qpi/vtt

For 210 bclk, I need to run 1.79 qpi/vtt which is really high.

Most everyone else is running 210 -211 bclk with under 1.4 qpi/vtt.

I guess I figure worst case, if the chip isn't any better can I always resell it at a little bit of a loss.

[Splave]

1.79 qpi/vtt

way too high it must be something else