Too much or too little voltage on 940 overclock?

dyrnwyn

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Mar 29, 2009
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Greetings,

I've got a 940 running @ 3.52 ghz (x160). Using Vista 64, Coolermaster V8, and some silverstones which move a lot of air. I just added a second video card to the setup (GTX 285) so the case environment has gotten, um, warmer. So I figured figured I'd try to bring down the voltage on my CPU some to bring it temperature down. my cpu floats @ about 40c +/-2c most of the time while idle...it's obviously better in the winter.

I have a pretty basic OC right now on a P6T6 WS Revolution ASUS board. I've only changed a few stats to get this speed:

bclk: 160
pcie freq: 100
CPU voltage: 1.20
QPI/DRAM Voltage 1.25
DRAM Bus: 1.64

I've had no problems with this setup. Runs Prime95 for hours and never crashes.

So I tried this one recently:

bclk: 160
pcie freq: 100
CPU voltage: 1.18125
QPI/DRAM Voltage 1.23125
DRAM Bus: 1.62


Things seemed like they were working pretty fine. Prime95 was not an issue.


Then I tried this:

bclk: 160
pcie freq: 100
CPU voltage: 1.175
QPI/DRAM Voltage 1.225
DRAM Bus: 1.62


And all hell broke loose. Bunch of crashes...basically had to revert to the original settings before I could get back to my 1.18 voltage without my machine giving me the finger.

My question is: would the 1.2/1.25 CPU/QPI voltages be described as "aggressive" for that overclock, or are they comparatively conservative...which is to say, it's about as low voltage as it should be at that speed and going lower, though cooler, will only lead to a ton of instability? I am new to this and don't really have any context for voltage versus OC in terms of mins and maximums. I did notice that Tom's 920 overclock for the AMD comparison (x172 @ 3.44ghz) took 1.296 volts, which seems comparably more sever of course, and which is actually what drove this question.

Thanks




 

spinny

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Jun 4, 2006
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Considering 1.2v is the standard voltage, no I would not call it 'aggressive'. The amount you will be able to go under 1.2v will amount to basically nil in terms of temps, so I would leave it.