GeForce 8800 GT 512MB vs Radeon HD 4870 512MB

Intro

Compare those specs to the Radeon HD 4870 512MB, which has a clock speed of 750 MHz and a GDDR5 memory frequency of 900 MHz. It also features a 256-bit bus, and uses a 55 nm design. It features 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8800 GT 512MB		105 Watts
Radeon HD 4870 512MB		150 Watts
	Difference: 45 Watts (43%)

Memory Bandwidth

As far as performance goes, the Radeon HD 4870 512MB should theoretically be much superior to the GeForce 8800 GT 512MB in general. (explain)

Radeon HD 4870 512MB		115200 MB/sec
GeForce 8800 GT 512MB		57600 MB/sec
	Difference: 57600 (100%)

Texel Rate

The GeForce 8800 GT 512MB is just a bit (approximately 12%) more effective at texture filtering than the Radeon HD 4870 512MB. (explain)

GeForce 8800 GT 512MB		33600 Mtexels/sec
Radeon HD 4870 512MB		30000 Mtexels/sec
	Difference: 3600 (12%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon HD 4870 512MB is a better choice, by far. (explain)

Radeon HD 4870 512MB		12000 Mpixels/sec
GeForce 8800 GT 512MB		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: Bandwidth is the max amount of information (in units of megabytes per second) that can be moved across the external memory interface in one second. The number is calculated by multiplying the bus width by the speed of its memory. If the card has DDR type memory, it must be multiplied by 2 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 anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied per second. This is calculated by multiplying the total amount of texture units 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 applied in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly write to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.