Wolfdale E8400

Q746A476
VID 1.125
Pack date: 07-01-2008
Period of usage until now - 3 months


Maximum voltage fed to the CPU:

vcore air - 1.75v
vcore LN2 - 2.05v
VTT - 1.55v
vPLL - 1.95v


Used for:

A number of air, dry ice and LN2 cooled sessions, for SuperPi 1M and 3D benchmarks, many hours each


Mobos:

-Asus Commando
-Asus Maximus Formula
-Asus Blitz Extreme
-Dfi Infinity P965


Initial behavior:

Orthos - 4000Mhz @ 1.28v (Maximus)


Behavior after high volts:

Orthos - 4000Mhz @ 1.33v (Commando)


Conclusion:

After applying extreme voltages (sometimes almost double than stock vcore)for a long period of time, going through temperatures between -150 and 65 degrees Celsius, the voltage needed to be Orthos stable at 4Ghz increased with 0.05v. This affects daily use, but until now I haven't noticed any changes in the behavior in extreme conditions, the CPU is still fit to run 3DMark at 5650Mhz with 1.9v at ~ -92/-100 degrees. The conclusion is logical and simple...If you care about 0.05v in daily use behavior, do not use the same CPU for extreme purposes. But if you bought the CPU for high end benchmarking, you shouldn't worry about this. This was always an issue, similar degradation happened to a lot of other CPU's that worked with extremely high volts in extreme conditions. We're not talking about something new, just that in the case of 45nm CPU's it happens earlier and it is easier to notice.


A few observations:

-vcore was measured with a voltmeter
-on Asus Commando at least, the voltage measured by in Hardware Monitor in bios (1605), the voltage shown by CpuZ 1.44.2 and the voltage measured with the meter are identical.