Sapphire Radeon HD 7790 Dual-X Review

As we’ve mentioned previously in a couple of other reviews, when overclocking a new breed of card, especially one that based on a new core design, we do find our self in a little grey area of knowing how far the card will overclock. Of course we have a rough idea, but its a large spread at that as some cores inherently will clock better than others.

Sapphires 7790 comes pre-overclocked, but 75MHz over stock is barely breaking a sweat and there has got to be much more to be found.

Starting off with the GPU core, and raising the clocks in increments of 20MHz and testing in 3DMark 11, we found the card to fall over at 1260MHz – bringing the clock back ever so slightly to 1255MHz proved a success. Next in line is the memory and like the core, sometimes we find that memory will overclock to the helm but in other cases it doesn’t – this all comes down to the core of the card and its power delivery. Like the core clock, we find the memory here has already been overclocked so we only have a ittle extra headroom left to find. Sure enough a little over 1760MHz we found artifacts starting to appear on scree indicating that all is not well and knocking this back a little gave us a perfect set of clocks for this card.

Overall we managed to achieve and extra 16.7% speed on the core clock and and extra 10% on speed on the memory clocks.

In a final test to ensure that that card is stable all round when overclocked and to see how the performance has risen in relation to the clocks, 3DMark 11’s Extreme preset is run again. Compared to stock where we got a score of 1688 points, overclocked we managed to get the card up to 1852, which works out as a ~10% gain in performance. Not at all bad for a budget card.