Overclocking
We weren't able to get too far on the overclocking front with KFA2's GTX 660 EX OC, but the amount of headroom can vary from one sample to the next, so we were pleasantly surprised to find that the Gigabyte GTX 660 OC went a bit further.
With little effort, it hit 1,110MHz on the core (that's base frequency, remember it'll Boost beyond that) and an effective 6,708MHz on memory. That's a bump of 77MHz and 700MHz, respectively.
With the overclock in place, we see a near-10 per cent increase in 1080p performance in certain games. Handy to know, but remember, overclocking performance varies from one card to the next; there's no guarantee you'll hit these speeds with every GTX 660 OC, though on the other hand, you may find your card goes even further.