Q6600 g0 p5b can't get stable at 2.9ghz

Black_Knight_MC

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Aug 19, 2005
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I have overclocked for many years and I read all the great things about the Q6600 G0, my temps are great and everything is fine. Well I finally decided I need to overclock for some better framerates and I am having the worst luck ever.

Asus P5B
Intel Q6600 G0 w/ Arctic Cooling Freezer 7 Pro
4x1GB Corsair 6400 (800Mhz)
XFX 8800GTX
2 HDs - WD 250 and 160 SATA drives
1 DVD/CD combo burner drive
PSU CORSAIR 620HX 620W

I just set the FSB to a mere 320mhz (~2880mhz for CPU) so as to allow my RAM to stay at 800mhz (4:5 ratio) and RAM is already at 5-5-5-15. CoreV set to 1.4625v and I get apps crashing every 5 min and prime95 errors within 1-2 minutes. I have no idea what to do because it fails so quickly. Mobo BIOS is newest, ver. 2001. The temps stay below 60C easy underload (at least as long as the stress test lasts), all cores idle around 37-40C in a 23C room. Ran Memtest86, 0 errors so RAM modules aren't faulty. When running stock settings I, of course, have no crashing of apps and prime95 ran for the 2 hours I let it go for.

I always thought an increase in core voltage is the way to solve instability but I hear people running this CPU at 3.2 at around 1.4 volts. I can't even get 2.9 stable at 1.465 volts????

If there is something I am forgetting please someone snap me into reality. Is my PSU not enough? it has 3 12V rails...

I am currently CLUELESS and need any suggestions, thanks.

Edit - I just tried setting core voltage to auto since many have gotten to 3.0-3.2ghz with Auto and Prime95 has 2 cores error within a minute. I think I got the worst Q6600 to roll of the line...

Edit 2 - Ok, looks like I may have found the issue, sort of. I am still set to Auto for the core voltage and for the hell of it changed the RAM divider to 1:1 causing the RAM to run at 640mhz instead of 800mhz. As I am writing this Prime95 is still going error FREE, 55-57C, for 30min, much better than the 20 SECONDS it took to error 2 cores. So my only guess is some of my RAM can't handle the increased FSB even when the divider causes them to keep running at their designed speed of 800mhz. I could always go buy another 4GB and goto 1066mhz RAM

http://www.newegg.com/Product/Product.aspx?Item=N82E16820227362

52 bucks plus tax, not a bad deal. If anyone thinks getting new RAM such as this is the likely solution (or if you DON'T think so as well) let me know.
 
Hi,
I don't think new memory is the asnwer, unless you've found it to be faulty.
DDR2 800 has plenty of headroom to overclock the Q6600.

And i would think for 3.0 ghz or so it's overkill on the Vcore @1.45, that's alot of juice and should not be required for the moderate OC.

I have a similar setup as you, albeit my MB is different (i have the Asus650i - P5N-E)
Some Asus MB seem to have a prob running all four dimms at full DDR2 800 speeds particularly when trying to OC. I believe it's something to do with 3-phase something or other, I'm not so hot with techno jargon.
I've got a nice (free) OC by simply changing mem to 667 and fsb 1333 for a 1:1 mem, running in unlinked mode.

My voltage is stock at 3.0 ghz which is 1.3v. Mem is just setup to use 2.0 v and timings listed on module at 4-4-4-12 (will mess around with tighter timings as it's running 333 instead of 400).However i do run the 4gbs in a 2 x 2gb config. Not the four dimms like you. NB 1.393.

Prime stable 12 hours. Hope that helps some.

K.
 
First, what is your VID?

Second, with an ACF7P, you should be able to reach up to 3.2 - 3.3 GHz. Any higher and you will need serious air cooling - Xig HDT S1283, TRUE, or something similar.

You should be able to reach 3.0 GHz or so with the stock voltage and HSF.
 

olddman

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Oct 29, 2008
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Hiya,

I have a P5Q-E motherboard with a Q6600. I'm not up on motherboards but I wouldn't think the difference is so great that they aint similiar in features.

Also let me say that I have DDR2 800 memory.

I'm not for sure if a 1:1 ration between the cpu and ram is more beneficial then keeping the ram at 800MHs. Mine is at 1:1 but ram is at 713MHs to get the 1:1. After reading the forums I thought a 1:1 was best way to go.

Now with that said, I got a very nice stable 3.2 overcloak on Q6600. First I set my ram to 4-4-4-12 @ 1.9v. This was specified on the ram chips themselves. I set CPU to 356 with the 9 mutiplier and left core voltage on auto. Booted up OK. CPU-Z showed voltage at 1.4v. Ran prime 95 for 22hrs. No errors. I then went back in and started lowering my voltage till it wouldn't post, then raised it back up, but anyway I ended up with 1.325v. Booted up. Ran prime95 for 42 hrs with no errors.

I know every piece is different even in the same mold, but I hope this helps
 

Black_Knight_MC

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Thanks for all the responses, and yes, I do realize my RAM SHOULDN'T be a problem. Perhaps like keith12 said, maybe the issue is with all 4 DIMMs being used. I SHOULD be able to run the RAM at 800mhz by using proper dividers. I am actually at 3.0Ghz at the moment (auto core voltage) , Prime95 2 hours stable (I just stopped it, wanted to test some games) , 55-57C. Played Cysis for several hours, the hottest a core got was 47C. Idle between 37-40C (Due to speedfan set to lower fan speeds when all cores are below 40C). RAM is at 667 mhz right now (1:1) and timings to auto (set itself to 4-4-4-12 on its own so thats good), FSB obviously at 333.

For now I am just going to keep pushing the FSB till Prime95 starts to fail, maybe loosen timings on RAM depending on how high I get. 3.4Ghz would be nice (1Ghz overclock).

Thanks again for the many responses. I love these forums.