i7 940 help

[VDubbAz]

First:
i7 940
3gig Kingston Hyperx 1800mhz L9 (will put more in once I get a stable clock)
ASUS P6T SE mobo
CoolMax Bronze 850w PSU
Win Xp Pro

I'm new to OCing and I've been scouring the boards for anything regarding 940 ocing. So far all I see is "Why did you buy that instead of a 920$?" Well I got this chip and board for free from someone who no longer needed it. I do know some of the basics for OCing such as the max - min settings but I've yet to see an actual OC guild for the 940 and it seem when I use the 920 guides I can't get a stable prim95 for more than an hour.
I haven't even gone into the more advanced settings I did the lower multipliers to find my max bclock and memory but it's the voltages that are the problem. Please if anyone can help a beginner w/o referring me to the same guide over and over and help directly I'd really appreciate it!

Thanks,
Jeh!

[Zero82z]

It's really not all that complicated. The voltages you need to worry about are the Vcore, QPI, DRAM, IOH, and CPU PLL voltages. The last two you probably won't have to touch and the DRAM voltage depends on what the manufacturer rated your kit at, so chances are you'll only be playing around with the Vcore and VTT.

First thing you have to do is aim for a reasonable overclocking target. I would recommend 3.4-3.6GHz just to get yourself started. The 940 has a multiplier of 22, so that means you'll need a Bclock of 155-165MHz or so to reach the speed you want. Make sure the Vcore, QPI, and DRAM voltages are all set manually and not on Auto, and then set your target base clock and see if the CPU will pass stress testing. If not, go back into the BIOS, slightly raise the Vcore, and try again. Rinse and repeat until you either get stability or until you find yourself using Vcore values that are higher than what you should need (you shouldn't require more than 1.3V for that). If you find yourself getting nowhere, start raising your QPI voltage gradually and see if that has an effect on stability. From there, it's basically just playing around with different values of voltages, base clocks, and multipliers until you find something that works. The one thing you have to keep in mind is that you should not use a Vcore or QPI voltage higher than 1.4V.

[ForTheGG]

If I'm not mistaken, the 940 has a 23x multi when using turbo. You should be able to force this multiplier with your boards BIOs, odd multipliers tend to be more stable. Your 940 is a C0 stepping most likely, so unless you're lucky your max stable overclock will be approx. 3.8GHz.

CPU Frequency is derived from the BLCK and the CPU Ratio. So, CPU Freq = Ratio x BLCK, at stock your 940 is 2.93GHz = 22 x 133MHz. Set your goal and adjust either the multiplier or the ratio, both should work.

It is important to note that raising the BLCK also raises a few other frequencies, namely RAM frequency and QPI. Thus to be stable, you must adjust those values as well.

[Zero82z]

Originally Posted by ForTheGG

Your 940 is a C0 stepping most likely

All 940s are C0. The model was discontinued before the D0 revision was released.

[VDubbAz]

I know the multi is 23 with turbo but from what I've read 21 gives the best results. Right now I'm 24/7 stable w/prim95
3.9ghz
186x21
Vcore 1.21875
DRAM 1.64 (my previous problems this chip C0 stepping wont do the full 900mhz clock so it's at 743 right now
QPi/DRAM Core V 1.25

I'm still tweaking the rest of the QPI frequencies I've set them at the lowest ratio for now but as soon as my WC system comes I'll start adjusting.
Also I live in Arizona where its normally 43C outside and about 25-27 inside, Yes its hot but its do damn expensive to go any cooler during the day. My idle temps with my coolmaster v8, are about 41c and 60-63 with prime95. Considering my ambient temps are normally higher are these decent temps? Or should I look at re-greasing the heatsink with something a little strong until my WC comes(4-6weeks)?

[CroSsFiRe2009]

Those are actually pretty good temps. Have you tried taking the chip higher?

[VDubbAz]

Not yet. I wanted to wait until I was WC before I pushed it any further. Right now I'm testing different fans for air and creating a new shroud with my g/f father who works for Honeywell in their aeronautical division. He helps design heat resistant systems for high speed jets etc... So I'm hoping him and another guy from his work help me out. It would be nice to put out something quality at low cost w/o having to worry if its just junk.