Core i7/X58 Overclocking Thread

[dejanh]

thats true, personally i expected more from the 965, they were $2k here in australia

Yeah, I am not going to lie but I am pretty pissed at the moment. I purposely bought a Core i7 940 because I figured they would be higher binned chips than the Core i7 920 and hence get better overclocks. I know this is not guaranteed, but at least in AMD world it held pretty true. However, not only can I not get better overclocks (tried 2 CPUs so far), but the i7 920 actually often beats my highest stable overclocks on air.

A couple of points I noticed...

(1) Lots of chips out there will not run 20x multiplier. Both of my Core i7 940 chips won't. Above or below that is fine.
(2) Voltage requirements and temps for same clocks are a complete crapshoot. My first i7 940 would heat up ~15C more than the one I use now for the same volts and clocks.
(3) Jumps in volts for additional few MHz are stupendously large (e.g., going from 200x19 to 200x20).
(4) Having 22x multiplier (23x turbo) on the i7 940 is actually a major hinderance in comparison to the i7 920 as running this chip with 4-cores/8-threads at 22x200 is basically not possible thereby making 23x200 practically impossible. Turbo sort of gives a multiplier for free, except that means nothing when you cannot run your chip at its default multiplier to allow for turbo in the first place.
(5) At theoretical top clocks assuming 200MHz BCLK (even) there is a 400MHz difference between top clock on i7 920 vs i7 940 which likely translates to at least 0.3-0.5V (likely more) difference in extra voltage needed to achieve stability which is again practically impossible as most regular i7 920 will already require too much voltage to run at their theoretical maximum of 200x21.

Overall, pretty pathetic. With the current state of affairs and unless you are a top-notch enthusiast going for the higher possible bench score with some amazing cooling there is no point in buying either the i7 940 or the i7 965 EE. Simply put, they are a waste of money.