GeForce 8800 GTS (G80) 320MB vs Radeon HD 3870 1GB

Intro

Compare all that to the Radeon HD 3870 1GB, which comes with core clock speeds of 775 MHz on the GPU, and 1125 MHz on the 1024 MB of GDDR4 memory. 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

Power Consumption (Max TDP)

Radeon HD 3870 1GB		106 Watts
GeForce 8800 GTS (G80) 320MB		143 Watts
	Difference: 37 Watts (35%)

Memory Bandwidth

As far as performance goes, the Radeon HD 3870 1GB should theoretically be just a bit superior to the GeForce 8800 GTS (G80) 320MB in general. (explain)

Radeon HD 3870 1GB		72000 MB/sec
GeForce 8800 GTS (G80) 320MB		63360 MB/sec
	Difference: 8640 (14%)

Texel Rate

The GeForce 8800 GTS (G80) 320MB should be a lot (about 99%) better at texture filtering than the Radeon HD 3870 1GB. (explain)

GeForce 8800 GTS (G80) 320MB		24624 Mtexels/sec
Radeon HD 3870 1GB		12400 Mtexels/sec
	Difference: 12224 (99%)

Pixel Rate

The Radeon HD 3870 1GB will be a lot (more or less 21%) more effective at anti-aliasing than the GeForce 8800 GTS (G80) 320MB, and also will be capable of handling higher screen resolutions more effectively. (explain)

Radeon HD 3870 1GB		12400 Mpixels/sec
GeForce 8800 GTS (G80) 320MB		10260 Mpixels/sec
	Difference: 2140 (21%)

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.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the largest amount of data (in units of megabytes per second) that can be transported past the external memory interface within a second. It's worked out by multiplying the interface width by its memory speed. If the card has DDR type memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.

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

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