** OFFICIAL ** Core i5 Overclocking Results/Tips Thread

[ArCElM]

Whats a safe VTT? is 1.3 OK? I am unsure what could be holding me back, I am prime stable at 3.8

vcore 1.27 BIOS / 1.30 Windows FULL LOAD.
RAM within spec.
VTT 1.25

I seem to just be completely unable to hit 4Ghz stable, even with 1.37 vcore, has my CPU just hit the MAX? or is there something I can try to see if I can get to 4Ghz.

Thanks,

Temps are fine also, well within spec at about 58-60 FULL load using my Corsair H50.

Specs Below.

[NoepZor]

I disabled Loadline calibration on my GD65 board, so the voltage doesn't drop under load anymore, but rises somewhat.

I used the following settings:

Vcore: 1.4v (Load: 1.42v)
Vddr: 1.65v
Vtt: 1.4v
PCH: 1.9v

I used QPI divider of 16 and mem 3. Intel EIST / Turbo and C1E were turned off.

I didn't manage tot get 4Ghz stable at these settings. Even 3.85Ghz was not prime stable, generating errors after a few seconds.

I'm running 3750mhz now @ 1.28vcore and 1.2vtt and it works just fine, no errors so far in Prime.

Does anyone knows what I can check to get my CPU to around 4Ghz ?

[woppy101]

here is my setups volts

Vcore: 1.408
LLC: enabled
VTT: 1,37V
Vdimm: 1,65V
Timings: 9-9-9-24 1T
QPI link: 3210

cooled by triple rad
full loads at around 59-61c

[Yamcha67]

Whats a safe VTT? is 1.3 OK? I am unsure what could be holding me back, I am prime stable at 3.8

vcore 1.27 BIOS / 1.30 Windows FULL LOAD.
RAM within spec.
VTT 1.25

I seem to just be completely unable to hit 4Ghz stable, even with 1.37 vcore, has my CPU just hit the MAX? or is there something I can try to see if I can get to 4Ghz.

Thanks,

Temps are fine also, well within spec at about 58-60 FULL load using my Corsair H50.

Specs Below.

I disabled Loadline calibration on my GD65 board, so the voltage doesn't drop under load anymore, but rises somewhat.

I used the following settings:

Vcore: 1.4v (Load: 1.42v)
Vddr: 1.65v
Vtt: 1.4v
PCH: 1.9v

I used QPI divider of 16 and mem 3. Intel EIST / Turbo and C1E were turned off.

I didn't manage tot get 4Ghz stable at these settings. Even 3.85Ghz was not prime stable, generating errors after a few seconds.

I'm running 3750mhz now @ 1.28vcore and 1.2vtt and it works just fine, no errors so far in Prime.

Does anyone knows what I can check to get my CPU to around 4Ghz ?

I had the same problem, I think we made a mistake getting an MSI board :P, anyway I was able to get 4ghz by setting the Core & VTT Voltage to Auto.. prime stable for 12hrs.. I've tried setting voltages manually and it seems one core always fails, I don't know why =/.. Auto seems to work for me tho.. you should give it a go.. hope it works for you..

[ArCElM]

v interesting, I get exactly that, one core always fails.

So VVT AND VCORE at AUTO? ive never heard of that before.

[keenan]

@ArCElM

Disable all your powersaving features and turbo mode...

Enable Load Line Callibration, set Vcore to 1.325V and VTT to 1.350V

Try that and tell me how it went...

[Yamcha67]

Hmm I knew it was motherboard, I will also try enabling load line calibration, maybe I can get over 4ghz out of my i5

[Capper5016]

I disabled Loadline calibration on my GD65 board, so the voltage doesn't drop under load anymore, but rises somewhat.

@ArCElM

Disable all your powersaving features and turbo mode...

Enable Load Line Callibration, set Vcore to 1.325V and VTT to 1.350V

Try that and tell me how it went...

I'm telling you, the loadline calibration on this board is wrong, "Disabled" is enabled, and "Enabled" disables it. If you set it to "Enabled" at that low voltage, its going to sag to about 1.25-1.26 and cause a BSOD. I think that 1.35 VTT is too high, try what I explained earlier....set the VCore to 1.33V and VTT to 1.3, with Loadline Calibration DISABLED, and you should have luck.

[Yamcha67]

On my MSI P55 GD65, I tried enabling Load Line Calibration with Vcore + Vtt set to auto what happens is prime fails and CPUZ reads the voltage at 1.36V, where as with Load Line Calibration Disabled CPUZ reads it 1.43V and 12hrs prime stable...

Does it only make a difference with manual volts?

[Capper5016]

Yes, its the same on "Auto" or manually setting the voltage. Loadline Calibration is just another name for VDroop. When its enabled, its supposed to keep the VCore from sagging under load.....unfortunately, its configured backwards in the BIOS and is confusing a lot of people.

Whats equally troubling is the voltage control on this board (MSI GD-65), it either sags terribly, or the voltage spike when the Loadline Calibration is actually doing its job is in my opinion, very unsafe. I'm not sure that its as simple as a new BIOS revision to fix the issue either.

[NoepZor]

I did find out this @ 4000Mhz:

When I test my system @ Prime95 blend mode: Errors after a few seconds
When I test it @ Prime95 small FFT (fits in cache, almost no mem used): 1,5 hours no errors (then I stopped the test).

I think my memory or motherboard/memcontroller is resisting. When I lower the CPU speed by the multiplier top 2400Mhz, then I also get errors in Prime95 blend mode.

My mem is running @ 1200Mhz 9-9-9-24 @ 1.65v, which is within its JEDEC specs (1333 @ 8-8-8-21 @ 1.5v is possible). Maybe it is incompatible with my motherboard/cpu somehow. @ 187 bclock and around 1122Mhz DDR it's working just fine.

[ArCElM]

My chip is sweet as on decent volts upto 3.6/3.8 but 3.9 and 4.0 is just not happening.

Currently at 3.8, vcore 1.27 BIOS, 1.304 FULL LOAD.

I think my chip has just hit its max tbh and I can;t complain about 3.8 on decent vcore.

[zsamz_]

if you dont need all 4 cores try 2 cores
clocks higher and much more bandwidth

[PolRoger]

I was doing a similar overclock on my X3440 and thought I would give it a try on my i5.
1.375v vcore set in BIOS with vdroop (LLC disabled) 181x21 turbo enabled (4 threads) and 181x24 (2 threads) with C-State enabled. In effect you get a 4.3Ghz dual core and a 3.8Ghz Quad. If you want to try this type of overclock I would recommend leaving C1E disabled at first to dial in your voltages for stability. With C1E enabled your voltages can drop quite low (0.988v) and will spool up on demand. You do need more vcore to stabilize the x24 multi then is required to run 4 cores at x21 multi. In my overclock at 3.8 I'm showing 1.352v/1.364v load in CPUZ. My board overvolts with C1E enabled and will show as high as 1.399v/1.411v in CPUZ while running SuperPi 1M and 32M.

[CARLOS*A1]

Hello I am overcloked cooler air with a Core Contac Freezer. I'm thinking about buying the Dragon F1... Dry Ice

4.476 Ghz Air.



Greetings

[cole2109]

How much is max voltage for 24/7 on H2O?
I don't know what to set on:
PCH voltage?
Voltage on CHA/CHB?
IMC voltage?
QPI fre?
CC Skew?

I have Asus P7P55D, I5@4250MHz vcore 1.416V, PLL 1.8V, IMC 1.225V, other on AUTO (prime stable).
Max BCLK on this settings is 217 .
What can i set to get more BCLK?

Max validation:
http://valid.canardpc.com/show_oc.php?id=792231

Hello I am overcloked cooler air with a Core Contac Freezer. I'm thinking about buying the Dragon F1... Dry Ice

4.476 Ghz Air.

24 multi? How?

[PolRoger]

24 multi? How?

Turbo and C State "enabled" should give you (x24) multi for two threads. http://www.xtremesystems.org/forums/...&postcount=139

[unclewebb]

The 24X multiplier that CPU-Z reports can be a little misleading. If you could eliminate all background processes, you would be able to get a constant 24X multiplier but in reality, you can't do this. There will always be background processes that become active and will drop your multiplier on a Core i5-750 down to 21. When running any sort of load, it will cycle constantly between 24 and 21 when C-States are enabled and will drop a lot lower than that at idle.

Run a single threaded bench and in the middle of it, have a look at RealTemp. It displays the average multiplier on your hardest working core and takes into account the constant multiplier cycling that's going on inside your CPU.

At idle when CPU-Z is able to show a 24X multi, the multiplier on the hardest working thread is nowhere near that high.

http://www.fileden.com/files/2008/3/...alTempBeta.zip

[CARLOS*A1]

Hello

disable the load line had calibbration.

cpu vtt 1.275v
cpu v core 1.418v

environment temperature 25 to 26Cº 12 am - 3 am I overclocked in day 30Cº 33Cº

low apologize- bad for my English.

Air
4.472 Ghz / 213 fsb x 21 / Memory 2130 Mhz / CAS 8 - 8 - 8 - 24 / SPI 2MB 20.750 Seg



Air
4.506 Ghz / 188 fsb x 24 / Memory 1880 Mhz / CAS 8 - 7 - 7 - 20 / SPI 2MB 20.812 Seg


Vinas

[Vinas]

Hello

disable the load line had calibbration.

cpu vtt 1.275v
cpu v core 1.418v

Air
4.987 Ghz / 525 fsb x9.5 / Memory 1750 Mhz / CAS 6 - 6 - 6 - 16 / SPI 2MB 22.437 Seg

Makes no sense to post your 8500 overclock TBH. Also please show us your load temps on your air cooler. They must be pretty high for those volts I'm thinking.

[ArCElM]

I dunno I think its just me maybe, and these forums are called 'XTREME SYSTEMS' but..

How come everybody is so happy to run above the max vcore?

1.4 vcore is the absolute max or you will damage your chip.

but I always recommend 1.35 and under for safety for the i5.

Does nobody actually know 1.4 is the MAX for these chips?

Why are people still using vcores from 2 chip generations ago and applying them to chips released 2-3 years later.

The idea of a good chip, or if you want to show off how good your chip is or your overclocking knowledge, its how far can you take your chip within the vcore limit or as low vcore as poss.

Infact there should be an E-PENIS thread created, 1.4vcore (in other words load or idle, vcore stays 1.4 or under) then everybody should post how high they got there chip to clock while remaining stable for a couple of hours on prime, (or some other decent stability test) pop out a screenshot and if your feeling kind tell everybody how you did it if its impressive.

That would be a really interesting thread.

But I only speak for myself when I say I could not give a rats ass that sombody can run superpi and 4.4Ghz when they are using more than 1.4 vcore, like wow, if I wanted to use 1.5vcore I dont rly have any doubts I could probably bust out a superpi run at 4.4 or something but how the hell does that help me.. it dont, and its not some fkn acheivement to go into the BIOS and turn up vcore.

Whats of interest to me is, how good other peoples chips are, and what they can do at CORRECT voltage and if there are any tricks to getting stability at lower vcores.

For example, if I was not stable at say 3.9 1.32 vcore, would there be something else can could effect stability other than turning up vcore coz we ALL KNOW the LESS vcore the BETTER.

WHO KNOWS I think I am just fed up of seeing ppl showing great clocks then u see somet stupid like 1.47 vcore in there cpu-z shot, and think WTF? POINTLESS and UNINTERESTING...

if I see sombody with 4.1Ghz and they are on 1.36vcore im like WOW fk me NICE CHIP how did u do that? THATS impressive and something to be shared.

[hokiealumnus]

Wow that's quite the rant there. Nice work avoiding the swear filters also. Can't come up with another word to express your point? Anyway...just because you find attempting to reach good clocks "pointless and uninteresting" does not mean others do. There are a lot of people who overclock because they enjoy benchmarking, using every last MHz they can squeeze out of their chips.

This is Xtreme Systems, where you will find that these people are closer to the rule than to the exception. Please refrain from insulting those that (god forbid) find such things interesting. There is a place for stability and for benching with max clocks. Can't we all just get along?

[cole2109]

@ArCElM just 4 u




This is MAX stable BCLK


At 214 BCLK PC freez after few minutes on Prime. 215, 216, 217 freez instantly when i run prime. But games runs OK

What can i do to get higher BCLK?

[unclewebb]

Here's what the datasheet says for the Core i5-700 and Core i7-800 series:

http://www.intel.com/design/corei5/documentation.htm



Unless I'm reading this wrong, absolute max voltage seems to be higher than 1.40 volts for these new CPUs. I guess we won't know for 6 months or so what the real maximum voltage should be for 24/7 use. By then, if an i5-750 has degraded, I'm sure there will be something new to buy like a 32nm replacement.

The maximum VID is listed as 1.40 volts but the actual maximum core voltage can safely go higher than this.

Edit: For comparison, here are the specs for the previous Core 2 8000 Series.



There seems to be more core voltage wiggle room with the new Core i generation of CPUs.
The Core i7-900 series is also rated at a maximum core voltage of 1.55 volts.

[ArCElM]

cole2109

LOL awsome nice chip! man I wish mine would do that, it does 3.8 stable at 1.3 but after that its not happy about much without allot more vcore.

unclewebb

quality post, and informative, although I think it was best I did NOT know that, thanks though I read max 1.4 somwhere and thought that was it, I MIGHT be more tempted to try 1.4vcore now where as before I was playing it safe with about 1.35 tops, cooling is decent ENOUGH its the corsair H50 which is about as good as a VERY good air cooler so, we will see, I really did want 4ghz out of this, I am a bit upset I am struggling so much.