Overclocking

Here we'll take a look at the overclocked performance of the GammaChrome S18 Nitro. bear in mind that the overclocked speeds are not representative of all boards of its kind, especially so as this is a pre-production board and there may be chip and board changes that have occurred since this board was manufactured and the eventually mass produced boards to be released.

The board tested here was able to overclock the core from its default speed of 450MHz to 483MHz, representing a 7% performance increase. PowerStrip, the only utility that we found could support overclocking on the S18 at the moment, could not overclock the memory rates and so these remain at the default of 450MHz.




Half Life 2 (FPS) 640x480 800x600 1024x768 1280x960 1600x1200
Default (450/450) 36.6 23.3 14.0 10.7 6.4
483/450 39.0 24.7 14.9 10.9 6.8
% Increase 6.6% 6.3% 6.4% 1.7% 6.7%
 
Half Life 2, 2x FSAA & 4x AF (FPS) 640x480 800x600 1024x768 1280x960 1600x1200
Default (450/450) 23.4 14.8 8.8 6.3 3.9
483/450 24.5 15.8 9.4 6.7 4.1
% Increase 4.6% 6.8% 6.5% 6.7% 6.7%
 
Doom3 (FPS) 640x480 800x600 1024x768 1280x1024 1600x1200
Default (450/450) 54.2 41.0 28.0 18.1 13.1
483/450 55.0 42.2 29.0 18.8 13.6
% Increase 1.5% 2.9% 3.6% 3.9% 3.8%
 
Doom3, 4x AF (FPS) 640x480 800x600 1024x768 1280x1024 1600x1200
Default (450/450) 49.0 36.9 25.6 16.9 12.4
483/450 50.2 38.0 26.4 17.3 12.9
% Increase 2.5% 3.0% 3.1% 2.3% 4.0%

With no memory clock increases Doom 3 is yielding up to a maximum of a 4% performance gain here. Half Life 2, on the other hand, is gaining very close to 7%, which is the equivalent of the core clock increase, and even doing so with FSAA enabled, which at 2x also requires twice the bandwidth - this shows how shader performance limited the the S18 in in this test and as shaders don't utilise much bandwidth the performance increase scale in-line with the core clock increase.