GeForce GTX 570 vs Radeon HD 3870 X2 1GB

Intro

Compare that to the Radeon HD 3870 X2 1GB, which has clock speeds of 825 MHz on the GPU, and 1126 MHz on the 1024 MB of GDDR4 memory. It features 320(64x5) SPUs as well as 16 Texture Address Units and 16 ROPs.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically speaking, the GeForce GTX 570 should be 5% faster than the Radeon HD 3870 X2 1GB in general, due to its higher data rate. (explain)

GeForce GTX 570		152000 MB/sec
Radeon HD 3870 X2 1GB		144128 MB/sec
	Difference: 7872 (5%)

Texel Rate

The GeForce GTX 570 should be much (about 66%) more effective at AF than the Radeon HD 3870 X2 1GB. (explain)

GeForce GTX 570		43920 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 17520 (66%)

Pixel Rate

The GeForce GTX 570 will be a little bit (about 11%) better at FSAA than the Radeon HD 3870 X2 1GB, and capable of handling higher resolutions without losing too much performance. (explain)

GeForce GTX 570		29280 Mpixels/sec
Radeon HD 3870 X2 1GB		26400 Mpixels/sec
	Difference: 2880 (11%)

Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the largest amount of information (counted in megabytes per second) that can be transferred past the external memory interface in one second. The number is worked out by multiplying the card's bus width by its memory speed. If it uses DDR memory, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This number is calculated by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.