XFX GF 8800GTX XXX Overclocked Video Card Review :: XFX GF 8800GTX 630M 768M Dual DVI TV XXX Edition Features

01-02-2007 · Category: Hardware - Video Cards

By Benjamin Sun
  • DirectX 10
  • Pixel Shader 4.0
  • Vertex Shader 4.0
  • 32-bit per color component HDR
  • Up to 16xQ FSAA
  • Up to 16x AF
  • Geometry Shaders
  • Physics Shaders
  • 681 Million Transistors
  • 90 nanometer low-k process

The G80 architecture was announced on November 8th, 2006, marking the launch of the first PC Unified Shader architecture, the first DirectX 10 architecture to hit the market, and is the 8th generation GeForce architecture on the market. GeForce 8800GTX has over 681 Million Transistors and is based upon the 90 nanometer low-K process from the TSMC fabs.

The XFX card has a clock speed of 630MHz, compared to the standard clock speed of 575MHz for the core clock. The memory clock on the card is 2GHz effective, meaning the card is about 10% overclocked on both the core clock speed and the memory clock speed. How that will play out on a card that is already CPU limited in many situations should be interesting to look at in the performance area of the review.

The 8800GTX has 128 Stream Processors that are grouped into 8 arrays of 16 Stream Processors each. The Stream Processors can do Pixel Shaders, Vertex Shaders, Geometry Shaders, or Physics Shaders and support DirectX 10 Pixel Shader 4.0 and Vertex Shader 4.0 specification. I've covered the many new features of the 8800GTX in previous 8800 reviews and will only provide the pertinent facts here.

Coverage Sample Anti-Aliasing is NVIDIA's new anti-aliasing type that is used with their 8x, 16x and 16xQ modes on their 8800 series cards. Coverage sampling combined with multisampling, takes extra coverage samples in the subpixel to determine if triangles intersect the subpixels at those sample points. If the extra coverage samples intersect they are used in combination with multisampling to produce the final outputted pixel. If they don't intersect, then it fallbacks to the lower MSAA mode without the extra samples.

8x AA is not true MSAA as you would expect, but 4x MSAA+4 extra coverage samples as described above. 16x AA is 4x AA+12 extra coverage samples and 16xQ AA is 8x MSAA+8 extra coverage samples. 16xQ AA is expensive to use, but provides the best possible image quality on the market today in graphics cards. 16x AA is virtually totally usable in most games, but the quality can vary between 4x MSAA and 16xQ and doesn't work well with stencil shadows.

XFX GF 8800GTX XXX Overclocked Video Card Review Golden Fingers

Golden Fingers

The 8800GTX is capable of running in SLI mode. SLI mode means that two or more graphics cards are daisy chained together to improve performance in games or other applications. All 8800GTX cards come with two SLI “Golden Finger” connectors, but only one of the “Golden Fingers” is required for SLI. This suggests the possibility of 3 cards, with one dedicated to Physics.