GeForce 8800 GTS (G80) 640MB vs GeForce GTX 570

Intro

The GeForce 8800 GTS (G80) 640MB uses a 90 nm design. nVidia has clocked the core frequency at 513 MHz. The GDDR3 RAM is set to run at a speed of 792 MHz on this specific card. It features 96 SPUs along with 48 Texture Address Units and 20 Rasterization Operator Units.

Compare those specifications to the GeForce GTX 570, which features a clock speed of 732 MHz and a GDDR5 memory frequency of 950 MHz. It also makes use of a 320-bit bus, and makes use of a 40 nm design. It is comprised of 480 SPUs, 60 Texture Address Units, and 40 Raster Operation Units.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the largest amount of information (counted in megabytes per second) that can be moved over the external memory interface within a second. It is calculated by multiplying the bus width by its memory clock speed. If it uses DDR RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This number is worked out by multiplying the total texture units of the card by the core clock speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip can possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.