GeForce 8800 GT 512MB vs Radeon HD 3870 1GB

Intro

Compare that to the Radeon HD 3870 1GB, which comes with core speeds of 775 MHz on the GPU, and 1125 MHz on the 1024 MB of GDDR4 RAM. It features 320(64x5) SPUs as well as 16 Texture Address Units and 16 Rasterization Operator Units.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8800 GT 512MB		105 Watts
Radeon HD 3870 1GB		106 Watts
	Difference: 1 Watts (1%)

Memory Bandwidth

The Radeon HD 3870 1GB should theoretically be much faster than the GeForce 8800 GT 512MB overall. (explain)

Radeon HD 3870 1GB		72000 MB/sec
GeForce 8800 GT 512MB		57600 MB/sec
	Difference: 14400 (25%)

Texel Rate

The GeForce 8800 GT 512MB will be much (about 171%) better at anisotropic filtering than the Radeon HD 3870 1GB. (explain)

GeForce 8800 GT 512MB		33600 Mtexels/sec
Radeon HD 3870 1GB		12400 Mtexels/sec
	Difference: 21200 (171%)

Pixel Rate

The Radeon HD 3870 1GB is quite a bit (about 29%) better at full screen anti-aliasing than the GeForce 8800 GT 512MB, and also will be able to handle higher resolutions while still performing well. (explain)

Radeon HD 3870 1GB		12400 Mpixels/sec
GeForce 8800 GT 512MB		9600 Mpixels/sec
	Difference: 2800 (29%)

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 (measured in megabytes per second) that can be moved over the external memory interface in a second. It is worked out by multiplying the bus width by its memory clock speed. In the case of DDR RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster 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 applied in one second. This is calculated by multiplying the total number of texture units by the core clock speed of the chip. The better this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip can possibly record to the local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the number of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on lots of 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.