GeForce 8800 GTS (G80) 640MB vs Radeon HD 4750

Intro

Compare those specifications to the Radeon HD 4750, which features a clock frequency of 730 MHz and a GDDR5 memory speed of 800 MHz. It also features a 128-bit memory bus, and uses a 40 nm design. It is made up of 640(128x5) SPUs, 32 TAUs, and 16 Raster Operation Units.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4750		75 Watts
GeForce 8800 GTS (G80) 640MB		143 Watts
	Difference: 68 Watts (91%)

Memory Bandwidth

Performance-wise, the GeForce 8800 GTS (G80) 640MB should in theory be a lot better than the Radeon HD 4750 overall. (explain)

GeForce 8800 GTS (G80) 640MB		63360 MB/sec
Radeon HD 4750		51200 MB/sec
	Difference: 12160 (24%)

Texel Rate

The GeForce 8800 GTS (G80) 640MB is just a bit (more or less 5%) better at anisotropic filtering than the Radeon HD 4750. (explain)

GeForce 8800 GTS (G80) 640MB		24624 Mtexels/sec
Radeon HD 4750		23360 Mtexels/sec
	Difference: 1264 (5%)

Pixel Rate

The Radeon HD 4750 is a small bit (more or less 14%) more effective at full screen anti-aliasing than the GeForce 8800 GTS (G80) 640MB, and also capable of handling higher resolutions better. (explain)

Radeon HD 4750		11680 Mpixels/sec
GeForce 8800 GTS (G80) 640MB		10260 Mpixels/sec
	Difference: 1420 (14%)

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 max amount of data (measured in megabytes per second) that can be transported across the external memory interface in a second. The number is calculated by multiplying the card's interface width by its memory clock speed. If the card has DDR type RAM, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster 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 can be processed in one second. This figure is calculated by multiplying the total number of texture units 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 in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.