Intel Core 2 Extreme QX6700 OC help Please! Cheers : D

[malice19]

try 333x9 instead - that'll give you 3GHz and let you know if you're hitting the ceiling of your chip at ~ 3.3GHz. Then you could try dropping back to an 8X multiplier and trying something like 375x8 which would also give you 3GHz, or even 400x8 for 3.2GHz and a 1600FSB. The one thing I will say, however, is that you need to be careful about the VRMs overheating. AFAIK there was only ever a B3 stepping for the QX6700, and that's the one that doesn't overclock as well (the G0 Q6600s were the ones that just kept overclocking!). I'd guess, based on that, that your chip may well top out at around 3.2GHz.

With s775, it's all about tweaking to get the best combination of

Tried as advised and yes it does work with 333x9 but 375x8 or 400x8 will not boot into windows. EDIT does work once i read you post again and took off Auto and set to 1600 : P

[scaryjim]

I'm still worried about your version of CPUz reading the FSB all wrong - something is definitely up there.

Still, if you can get it to do 400x8 I'd stick with that - decent CPU clock and excellent on the FSB

[malice19]

Have you tried dropping back to a 10x multiplier and pushing the FSB to 333MHz? With s775 systems you want the FSB as high as possible as all the memory transactions have to go across that bus, so the higher you can get the FSB the better performance you're likely to see. With IMCs on modern CPUs it doesn't make that much difference, but back in the old FSB days a higher FSB was always the way to go...

And looking at it, 11x273 should only be 3.003GHz, not 3.3GHz. I noticed in some of your other posts the CPUz FSB doesn't match the FSB you say you've input. I'd check that you've for the right drivers for your motherboard installed - your spec says P45DE but I notice that the CPUID Hardware monitor says P43DE. Also, if your CPU cooler is set to low I'd turn it up, as you may find that @ 70°C you'll get thermal throttling on the CPU (I'm pretty sure this kicked in around 70 on my old Q6600). That may then let you push the overclock further - and like I said above, the best thing to do is drop the CPU multiplier down, find the fastest FSB the board will run at, then slowly increase the multiplier until you get instability. Even if it leaves you at a lower overall CPU clock, a faster FSB will be better for performance.

333 x10 Gets into windows then BSOD : (
So even though CPU z is saying im only getting a core clock of 2.5Ghz its still worth it as im getting higher FSB?

Only worry i have with this setting is Prime 95 when testing all cores errors on

[Dec 19 16:55] Worker starting
[Dec 19 16:55] Setting affinity to run worker on logical CPU #0
[Dec 19 16:55] Beginning a continuous self-test to check your computer.
[Dec 19 16:55] Please read stress.txt. Choose Test/Stop to end this test.
[Dec 19 16:55] Test 1, 4000 Lucas-Lehmer iterations of M19922945 using FFT length 1024K.
[Dec 19 16:55] FATAL ERROR: Rounding was 0.5, expected less than 0.4
[Dec 19 16:55] Hardware failure detected, consult stress.txt file.
[Dec 19 16:55] Torture Test completed 0 tests in 0 minutes - 1 errors, 0 warnings.
[Dec 19 16:55] Worker stopped.

Does this mean even though it has not crashed is not working correctly with 8x 400?

Cheers

[scaryjim]

Hmmm, not sure about the Prime95 test - you might be best googling that one.

As to CPUz, if the setting in BIOS is 400x8 you should be getting 3.2GHz, but CPUz seems to be reporting it as 8*320. Might be worth reinstalling CPUz and checking again, because either the OC tools are showing it wrong or CPUz is, and either that way that suggests that something's up. Along with the Prime95 test as well, it could indicate that there's a problem with some item of hardware... might be worth going back into the BIOS, setting *everything* to AUTO, and then doing a CPUz shot (while running something like Prime95 or wPrime) to check what CPUz reports as the default settings. You CPUz shot in the first post is way off what I'd expect the default settings to show as (should be core speed 2666MHz, multiplier x10, Bus speed 266MHz, rated FSB 1066MHz). If CPUz shows something different from that with all the BIOS settings at AUTO, there's something wrong (and personally I'd be pointing me finger at the motherboard...).

[jim]

Yeah Prime95 is indicating a failure there, you've got an unstable OC.

[scaryjim]

Yeah - go back to stock settings and test everything - including running Prime95. That'll help you work out if the overclock is the problem, or if it's something else. Like I said, I'm not entirely happy about your CPUz readings at stock: it might be that you've got something that's starting to show its age