GeForce 8800 GTS (G80) 640MB vs Radeon HD 3850 X2

Intro

Compare those specs to the Radeon HD 3850 X2, which features core speeds of 668 MHz on the GPU, and 828 MHz on the 512 MB of GDDR3 memory. It features 320(64x5) SPUs along with 16 TAUs and 16 ROPs.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the Radeon HD 3850 X2 is 67% faster than the GeForce 8800 GTS (G80) 640MB overall, because of its higher bandwidth. (explain)

Radeon HD 3850 X2		105984 MB/sec
GeForce 8800 GTS (G80) 640MB		63360 MB/sec
	Difference: 42624 (67%)

Texel Rate

The GeForce 8800 GTS (G80) 640MB is a small bit (about 15%) faster with regards to anisotropic filtering than the Radeon HD 3850 X2. (explain)

GeForce 8800 GTS (G80) 640MB		24624 Mtexels/sec
Radeon HD 3850 X2		21376 Mtexels/sec
	Difference: 3248 (15%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon HD 3850 X2 is a better choice, by far. (explain)

Radeon HD 3850 X2		21376 Mpixels/sec
GeForce 8800 GTS (G80) 640MB		10260 Mpixels/sec
	Difference: 11116 (108%)

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 maximum amount of information (measured in MB per second) that can be moved past the external memory interface within a second. It is worked out by multiplying the interface width by the speed of its memory. In the case of DDR type RAM, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly write to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.