GeForce 8800 GTS (G80) 640MB vs Radeon HD 4770

Intro

Compare all of that to the Radeon HD 4770, which features a GPU core clock speed of 750 MHz, and 512 MB of GDDR5 memory running at 800 MHz through a 128-bit bus. It also is comprised of 640(128x5) SPUs, 32 TAUs, and 16 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4770		80 Watts
GeForce 8800 GTS (G80) 640MB		143 Watts
	Difference: 63 Watts (79%)

Memory Bandwidth

In theory, the GeForce 8800 GTS (G80) 640MB should be 24% quicker than the Radeon HD 4770 in general, due to its greater bandwidth. (explain)

GeForce 8800 GTS (G80) 640MB		63360 MB/sec
Radeon HD 4770		51200 MB/sec
	Difference: 12160 (24%)

Texel Rate

The GeForce 8800 GTS (G80) 640MB will be a little bit (more or less 3%) more effective at texture filtering than the Radeon HD 4770. (explain)

GeForce 8800 GTS (G80) 640MB		24624 Mtexels/sec
Radeon HD 4770		24000 Mtexels/sec
	Difference: 624 (3%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 4770 is the winner, but not by far. (explain)

Radeon HD 4770		12000 Mpixels/sec
GeForce 8800 GTS (G80) 640MB		10260 Mpixels/sec
	Difference: 1740 (17%)

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: Bandwidth is the largest amount of data (counted in MB per second) that can be transported over the external memory interface in a second. It is calculated by multiplying the interface width by the speed of its memory. In the case of DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the 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 can be processed per second. This figure is calculated by multiplying the total texture units of the card by the core speed of the chip. The higher the texel rate, the better the graphics 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 most pixels that the graphics chip can possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.