Pentium D 940 Voltage Questions.

Hey. I have a Pentium D 940, and a Asus P5N32-Sli Deluxe. The stock vCore that it uses when I'm in windows is 1.216v or something to that affect. I just want to know what are "safe" vCores to use on this CPU. I have Water Cooling, so the temps should stay low. But i need a little help in overclocking this sucker. Ive gotten it to 4.0Ghz, but I had the vCore up pretty high, and had my mem at like 2.3v @ 4-4-4-8 900Mhz. So any advise, anyone whos used this CPU and overclocked it like a champ, anything i would love . That would be great. Ive seen this CPU up really high, but this board kinda sucks for... well... everything. But i want to get the best out of this CPU that i can.

Thannnnks in advance
MERKi[N]

I've been to 1.35 on my D 920, but my PSU is holding me under 3.5 GHz so I wouldn't really know if it would help you or not.

I've had my 940 up to 1.5V in bios without problems. However, temperatures get high at that voltage.

-GearShift3r

I went up as high as 1.65v but that was on water cooling. Now im air coolig with on a D950.

Nominal voltage from spec sheets are 1.25v - 1.4v with 1.55v max. Note that the 1.55v is a max overshoot value. Your not meant to stay there for very long. So they are the definite safe voltages but spec sheets are for stock operation and sometimes to achieve a higher overclock you will need more volts.

Just because you have it cool enough does not mean you are not causing damage though. I've read that with higher volts a thing called electron tunneling can happen which can degrade your circuit paths and also electromigration which is electrons gaining enough energy to jump on to an adjacent circuit.

It also depends on how long you want your chip to last. Stock voltage ratings are usually based on your chip lasting 10 years. Overclocking and overvolting may just knock a few years off that but by then you probably have upgraded anyway.

I've had my 950 to 4.3ghz stable on stock volts and probably the highest 24/7 setting I will use is 1.42v for higher overclocks.

I see. So i take it 1.7v is a no no. I'll keep that in mind when i get my new PCB. The thing was jerry rigged in the first place, but eh we'll see. The thing is, the machine (with old cpu) wouldnt post at 4Ghz under 1.7 volts... but that old CPU could have been flawed or something. Thanks for all the comments

-MERKi[N]