Can't get Q6600 stable above 333Mhz FSB

[IndieRock13]

Hey, I just got my computer built yesterday and set into overclocking it. Here are the specs:

Cooler Master CM-690 Case w/ 4 fans
520W PSU w/ 28 amps on 12V rail
Asus P5K Mobo
Q6600 w/ G0 stepping
Arctic Cooling Freezer 7 Pro Heatsink
A-Open Extreme 2GB DDR2 SDRAM - 800+ Mhz 4-4-4-12
EVGA nVidia GeForce 8800GTS 320MB SuperClocked

So I got it all put together and decided to try some overclocking after I got it set up. I ran Prime 95 25.4 for about 20 minutes and it was a nice cool 48C average. Went into BIOS and turned off all of the powersaving options, set the RAM to a defined 4-4-4-12, and set the FSB to 333Mhz with the RAM also set to 667 so it was 1:1. I set the VCore voltage to 1.365.

Booted up and everything went great. Ran Prime 95 for 8 hours and there were no errors. Here is where my confusion starts. The temperatures never got above 56C during the entire test. Two core averaged 56 and the others 55. This was measured with SpeedFan with the +15C modifier on each core as well as with CoreTemp. They disagreed a bit like usual but averaged around the same. CoreTemp said it got up to 59 on a couple of core.

These are perfectly acceptable temps though, especially for the G0 stepping. So I thought, ok, I should have some success going even higher.

I've tried FSB of 350, 360, 370, 380, and 400. I left the RAM scaled to 1:1 and kept the timing at its rated 4-4-4-12 at 2.1V (which it is rated at) and also tried it with 5-5-5-15. No matter what I've done though, windows starts up fine and everything is dandy, but Prime 95 errors out in the first minute on at least one core, saying "rounding returned 0.5, expected less than 0.4. Hardware failure detected"

I kept the VCore at 1.365 the whole time, which is the upper limit of the CPU's limit that I'm comfortable with. Even the slight upping of the FSB to 350 caused it. The temps stayed normal at around 58 or so. The G0 I had heard was fine at least until 70C. It seems like the RAM has to be on 667 or 800 for it to work at all (although the 400 FSB caused a system hang on XP boot so I can't really confirm that except that 333 is working.)


What could my problem be? The RAM? Just can't go higher with the CPU even though temps are fine?


*scratches head*


I've seen people getting their Q6600's to 3.4 at ~1.37v and given my heat it seems surprising that I'm not having the same luck. I'm a newbie at this so maybe I'm not doing something right...

Intel's stats suggest no higher than 1.37v for the q6600 so I'm not sure I want to push it any higher. Any thoughts on the safety of doing so?

 

[itotallybelieveyou]

well... if it's new build you should wait a week at least for paste to set in. The ram at 400 is the recommended clock so it cant be the RAM. The I have the arctic freezer too and my e6600 cant go over 3.33 ghz. try timing at 5-5-5-12? heard it's good for ocing. I don't have deep understanding of overvoltaging... but i do know that 1.6v is the highest safe. Overclocking E6600s i start my vcore at 1.4v so Q6600 should be fine. maybe it's the software's problem? try reinstalling the Prime95? if everything runs, smells, sounds fine. it's fine.

 

[Guest]

As posted above, wait a week for the paste to set, then try.

 

[IndieRock13]

Cool. My lack of patience is quite often my downfall =S

Wish I could set my memory divider so my ram was running a lower speed than the CPU FSB, but I can't with the P5K. Just wanna test the ram because I read in another forum someone was having trouble with their ram having to be set at 667 or 800 to be stable.

I do kinda doubt it's the ram though if Win XP continues fine without a hitch.... although it sometimes hangs with a blank screen before loading up the XP loading bar after I've messed with the ram's settings.