Confused about Vcore values

Yeggstry

Yeggstry

Yeggstry

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Joined
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Reading, UK
Hi guys,

I'm currently overclocking my Q6600 and I'm up to 3.2GHz. However, I've set the Vcore in the BIOS to 1.3V, but both CPU-Z and Asus PC Probe II are saying the Vcore is at 1.216 - how can that be?! Is there any other program that will show me a decent voltage for this.

I've just run prime stable for 30 mins and it seems fine, I'll do a full test overnight but I was wondering if its worth me just going straight for 3.6GHz, use my machine until tonight then I can do a full 8 hours stress test.

For 3.2GHz, my temps are: 60,60,51,51 (yes I know I need to lap it :p). The settings in the BIOS I have changed are:

FSB: 355
Vcore: 1.3000V

I'm surprised at how easy it is to overclock :)
 
Ah ok. Thanks :)

I've just gone to 3.6GHz @ 1.368V, however I'm getting this in prime. I would guess that I need to up the voltage?

[Apr 12 16:17] Work thread starting
[Apr 12 16:17] Beginning a continuous self-test to check your computer.
[Apr 12 16:17] Please read stress.txt. Choose Test/Stop to end this test.
[Apr 12 16:17] Test 1, 800000 Lucas-Lehmer iterations of M172031 using FFT length 8K.
[Apr 12 16:17] FATAL ERROR: Rounding was 0.5, expected less than 0.4
[Apr 12 16:17] Hardware failure detected, consult stress.txt file.
[Apr 12 16:17] Torture Test ran 0 minutes - 1 errors, 0 warnings.
[Apr 12 16:17] Work thread stopped.
 
Yip. We need that system super stable ;) Up the voltage to 1.4v. You'll likely have to go even higher.
 
Ok, got it up to 1.4v now, its running at the limit heat wise - 73/73/63/63. After I get it stable for 30 mins I may see how much lower I can get the Vcore, I'd rather have it below 70C :)
 
70's fine for a Q6600. But I would let Prime run for a few hours if you're intending to Fold on that rig. It'll need to be rock solid. And your Folding temps will be lower than Prime temps anyway.
 
Yeah I figured :p Was surprised because I checked the base of the TRUE before I fit it and it seemed flat. I think if I lap it in the future I'll splash out and get some Arctic Silver 5 as well - the stuff I have at the moment is Arctic Silver 3 and is about 5 years old.

EDIT: It failed about 15 minutes in :/ upping the voltage then :)
 
Yeggstry said:
Yeah I figured :p Was surprised because I checked the base of the TRUE before I fit it and it seemed flat. I think if I lap it in the future I'll splash out and get some Arctic Silver 5 as well - the stuff I have at the moment is Arctic Silver 3 and is about 5 years old.

EDIT: It failed about 15 minutes in :/ upping the voltage then :)
Click to expand...

Raise your nb/mch and fsb/vtt volts by 0.1v too.
 
Does PC Probe read them? If not then set the nb/mch voltage to ~1.45v, and the fsb/vtt to 0.1v higher than its lowest setting. You can try to lower them once you have finished clocking the CPU.
 
OK, thanks mate :) I upped the Vcore a couple of notches (think it was 1.41V) and its gone up to 74/74/65/65, but its been prime stable for nearly an hour now :) Hopefully it will be as good overnight.

The voltages reported by PC Probe are:
Vcore 1.31v
SB 1.09v
SB2 1.55v
FSBT 1.47
DRAM 1.98
DRAM Ref 0.99v
NB 1.65v

Temps are:
NB: 45C
SB: 38C
CPU 57 (in Core Temp 74/74/65/65).
 
Last edited:
I just noticed that the RAM that I have has a test voltage of 2.0-2.1 V - should I be manually setting the DRAM voltage to 2.0/2.1v in the BIOS? Could that be part of the problem?

I moved the overclock back down to 3.2GHz @ 1.4v and I've had one reboot but that was after hours of folding :) I'll have another try tomorrow to see what happens.
 
Well your vdimm is already set to 2v going by one of your posts above ('DRAM 1.98'). Tho 2.1v wouldn't be a bad idea til you've finished clocking .
 
Ok, this is interesting.... I'm currently on 3.2 @ 1.4v and I upped the DRAM to 2.1 and manually set the timings. Before I changed the DRAM voltage I had prime on and music in the background and the music was crackly - now it isn't. I'm willing to bet that the RAM didn't have enough voltage, as its been fine for about 3.5 hours now :) I'm now tempted to try 3.6 @ 1.4 tonight.

I haven't changed the NB or FSB voltage yet partly because of the comments I've seen in other threads that getting it wrong on the NB voltage may screw your board. I'd rather not do that, unless I should manually set them in case the auto settings are making the voltages too high :) I can set the voltages to the following in the BIOS:

FSB 1.20 - 2.00 in 0.02 increments
NB 1.25 - 1.85 in 0.02 increments
 
Well I tried 3.6 @ 1.4 and it didn't last very long :D I decided on bringing it down a bit as I don't want to be messing with the overclock during the week when I should be folding :) Its now prime stable at 3.4 @ 1.4v which will do for me this week, will try and eek a bit more next weekend :)
 
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