GeForce 8800 GTS (G92) vs Radeon HD 3870 X2 512MB

Intro

Compare those specs to the Radeon HD 3870 X2 512MB, which uses a 55 nm design. ATi has set the core frequency at 825 MHz. The GDDR3 RAM works at a frequency of 900 MHz on this specific model. It features 320(64x5) SPUs along with 16 Texture Address Units and 16 ROPs.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon HD 3870 X2 512MB should in theory be much faster than the GeForce 8800 GTS (G92) overall. (explain)

Radeon HD 3870 X2 512MB		115200 MB/sec
GeForce 8800 GTS (G92)		62080 MB/sec
	Difference: 53120 (86%)

Texel Rate

The GeForce 8800 GTS (G92) should be much (approximately 58%) more effective at texture filtering than the Radeon HD 3870 X2 512MB. (explain)

GeForce 8800 GTS (G92)		41600 Mtexels/sec
Radeon HD 3870 X2 512MB		26400 Mtexels/sec
	Difference: 15200 (58%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 3870 X2 512MB is superior to the GeForce 8800 GTS (G92), and very much so. (explain)

Radeon HD 3870 X2 512MB		26400 Mpixels/sec
GeForce 8800 GTS (G92)		10400 Mpixels/sec
	Difference: 16000 (154%)

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 max amount of information (in units of megabytes per second) that can be moved past the external memory interface in one second. It's worked out by multiplying the bus width by its memory speed. If the card has DDR RAM, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range 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 is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The better the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the most pixels the video card could possibly record to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel 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 ability to reach the max fill rate.