Originally Posted by
MpG
It would also be horribly depressing. Nothing like realizing that your $400 WC system got you less than 100Mhz over an air cooler. :D
Although seriously, regarding the 10*C=2% improvement, quite often, I think you run into temperature limitations (i.e. thermal throttling) before you technically hit that limit. What the water cooling also does does is give you the headroom to increase voltage/frequency, to reach the chip's limits without running into temperature walls (i.e. GTX480). And that's something that's a little harder to put into chart form.