GeForce 8800 GT 256MB vs Radeon HD 4770

Intro

Compare all that to the Radeon HD 4770, which has clock speeds of 750 MHz on the GPU, and 800 MHz on the 512 MB of GDDR5 RAM. It features 640(128x5) SPUs along with 32 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4770		80 Watts
GeForce 8800 GT 256MB		105 Watts
	Difference: 25 Watts (31%)

Memory Bandwidth

The Radeon HD 4770, in theory, should be a little bit faster than the GeForce 8800 GT 256MB in general. (explain)

Radeon HD 4770		51200 MB/sec
GeForce 8800 GT 256MB		44800 MB/sec
	Difference: 6400 (14%)

Texel Rate

The GeForce 8800 GT 256MB is quite a bit (approximately 40%) faster with regards to anisotropic filtering than the Radeon HD 4770. (explain)

GeForce 8800 GT 256MB		33600 Mtexels/sec
Radeon HD 4770		24000 Mtexels/sec
	Difference: 9600 (40%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon HD 4770 is a better choice, by far. (explain)

Radeon HD 4770		12000 Mpixels/sec
GeForce 8800 GT 256MB		9600 Mpixels/sec
	Difference: 2400 (25%)

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 max amount of data (in units of megabytes per second) that can be transported past the external memory interface in one second. It's worked out by multiplying the card's interface width by its memory speed. If it uses DDR type memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher 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 number of texture map elements (texels) that are applied in one second. This is worked out 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 handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly write to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. 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 rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.