Overclocking C2D e6750 Woes

[MattB]

I got an Intel C2D e6750 that can go to 3.5GHz but it isn't stable, it BSOD after 10 minutes using Orthos. But here's the thing, when I go back to 3.4, 3.2, or even 3.0, I get the same result. I've adjusted voltage all up and down the range and get the same result.

I've done memtest86 overnight at all 4 speeds listed above and it is stable, so I'm sure it's not my memory. It can't be heat because it is below 55C at 3.5GHz at full load. Nothing is stable except at stock speed. It can't be the motherboard because like I said, any FSB speed above stock should work fine.

So am I looking at a power supply that can't handle the overclock? How can I be sure it is the power supply that is the issue? Or am I overlooking something?

Here's my specs:

OCZ StealthXStream 600W PSU
Intel C2D E6750 Conroe 2.66GHz processor
EVGA LGA775 NVIDIA nForce 650i Ultra mobo
2GB G.Skill 240pin DDR2 800 PC26400 memory
Gigabyte GeForce 8800GTS 640MB video card
Arctic Cooling Freezer 7 Pro HSF

 

[cmdrdredd]

it's your Motherboard. The Nvidia based boards are hard to overclock.

 

[zach0624]

it sounds like your mobo but the 600 series should be better. the 680i should do much better though. also if you don't want sli get a p35.

 

[SerpentRoyal]

Use CPUz to confirm that memory is running at 1:1 divider. Manually set Vdimm to 2.1V with 5-5-5-15-2T timing. That MB runs hot and requires additional cooling at NB/SB.

 

[MattB]

Originally posted by: SerpentRoyal
Use CPUz to confirm that memory is running at 1:1 divider. Manually set Vdimm to 2.1V with 5-5-5-15-2T timing. That MB runs hot and requires additional cooling at NB/SB.

I've been meaning to put a fan on the heatsink over the NB and SB. The thing that irks me is that the manual came with no manual, and the one on eVGA's site is for a different revision, so it isn't accurate. I'm pretty much left in the dark for a lot of things on this mobo and having to rely on past experience.

I have tried your method with the VDIMM and loose memory timing, but as mentioned in my original post, not much luck.

I've stuck a boxed fan right up against the side of the case with the cover off and set it on medium, and even then didn't get positive result with overclocking beyond stock speed. I thought that would help if the NB/SB were the culprit in this case.

 

[SerpentRoyal]

You may need more Vcore. Try 1.46 to 1.48.

 

[bryanW1995]

what are your idle temps? Are you using the 15c offset? I load at 57c at 3.6 / 1.53 v using a tuniq tower. the ac freezer should load much higher than mine at such a high oc. If you are hitting 70c instead of 55 then you might have your answer.

 

[DAC21]

"That MB runs hot and requires additional cooling at NB/SB"


My thoughts as well