Intel Core i7 990X Hexcore 1366
For testing purposes we're gathering the various Intel chips together for a final showdown, although as we know there are many people who will wonder why it's worth spending so much on a CPU, we're also including the latest P67 processor for you.
Intel Core i7-990X
Zotac GTX580 AMP!
ASUS Rampage III Extreme
Muskin Joule 1200w
6GB Mushkin Redline
Windows 7 Ultimate x64
As always the first task is to seek out the maximum stable BCLK, which in the case of our 990X was 220.5MHz. This should give us plenty to play with.
Now as a rule of thumb once you find your maximum BCLK its generally difficult to get a high usable overclock with it, the 990X is one of the few processors that quash this rule as we managed to get a 4.8GHz overclock using that 220BCLK in conjunction with a 22 multiplier at just 1.4v.
And indeed it did. 200x20 is so easy and capable of running on such low volts that you could probably dispense with your power supply and just rub a balloon across your sweater now and again. Not strictly true, but away from the bleeding-edge overclocks the 990X definitely isn't a power-hungry monster.
However we're here for the big numbers, and after much sweating and tweaking the best I could manage was 5.2GHz, 208x25 with a vCore of 1.521v. Obviously this isn't something you would want to run 24/7 though.
For benchmarking purposes we're running our 990X at a utterly stable 4.7GHz. 204x23, with a 1.45v CPU vCore. 4.7GHz of Hex-Core goodness sir? Don't mind if I do.
Just for the sake of finding out we also set about finding the lowest stable volts that the 990X needed for a 200x20 4GHz overclock, the 970 needed 1.25v the 980x was thirstier wanting 1.35v but the 990X required a mind blowing 1.185v to be Prime95 stable! With these low volts and being cooled by the trusty NH-D14 temps did not go over 55c at full load over an 8 hour test period!