Despite having the same five vertex shaders and 256-bit memory interface, the GS has 12 pixel pipelines, four fewer than the 6800 GT. Yet, nVidia claims that the GS is faster than the GT. How is this possible? This is due to the GS possessing much greater clock speeds, with the reference card running at 425MHz core and 1GHz memory, compared to 350MHz, 1GHz for the standard GT. The reason nVidia is able to push the cards clock speeds is due to the fact that the GS is now based on nVidia NV42. This means that it’s now a native PCI Express part built on a 110nm process, rather than the 130nm process of the GT with an AGP to PCI Express bridge.
The GS does what it says on the tin, offering GT class performance but at reduced cost and with real overclocking potential. At around £165 on the street it’s looking like nVidia might be able to claim back that middle-tier performance ground, especially with Shader Model 3 support helping it to outdo ATI on the feature count.
Published in: Graphics Cards on 2005-11-11