GeForce 8800 GTS (G80) 640MB vs Radeon HD 4870 512MB

Intro

Compare those specifications to the Radeon HD 4870 512MB, which has core speeds of 750 MHz on the GPU, and 900 MHz on the 512 MB of GDDR5 memory. It features 800(160x5) SPUs along with 40 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8800 GTS (G80) 640MB		143 Watts
Radeon HD 4870 512MB		150 Watts
	Difference: 7 Watts (5%)

Memory Bandwidth

In theory, the Radeon HD 4870 512MB should be 82% quicker than the GeForce 8800 GTS (G80) 640MB in general, because of its higher data rate. (explain)

Radeon HD 4870 512MB		115200 MB/sec
GeForce 8800 GTS (G80) 640MB		63360 MB/sec
	Difference: 51840 (82%)

Texel Rate

The Radeon HD 4870 512MB should be quite a bit (approximately 22%) faster with regards to AF than the GeForce 8800 GTS (G80) 640MB. (explain)

Radeon HD 4870 512MB		30000 Mtexels/sec
GeForce 8800 GTS (G80) 640MB		24624 Mtexels/sec
	Difference: 5376 (22%)

Pixel Rate

The Radeon HD 4870 512MB is a bit (approximately 17%) better at anti-aliasing than the GeForce 8800 GTS (G80) 640MB, and also should be capable of handling higher screen resolutions without losing too much performance. (explain)

Radeon HD 4870 512MB		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 maximum amount of information (measured in megabytes per second) that can be transferred across the external memory interface within a second. The number is calculated by multiplying the interface width by the speed of its memory. If the card has DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The better 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 texture map elements (texels) that are processed in one second. This is calculated by multiplying the total number of texture units of the card by the core clock speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly record to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as 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, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.