GeForce GTX 460 2GB vs Radeon HD 4870 512MB

Intro

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

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4870 512MB		150 Watts
GeForce GTX 460 2GB		160 Watts
	Difference: 10 Watts (7%)

Memory Bandwidth

Both cards have exactly the same memory bandwidth, so in theory they should have the same performance. (explain)

Texel Rate

The GeForce GTX 460 2GB is much (more or less 26%) more effective at AF than the Radeon HD 4870 512MB. (explain)

GeForce GTX 460 2GB		37800 Mtexels/sec
Radeon HD 4870 512MB		30000 Mtexels/sec
	Difference: 7800 (26%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the GeForce GTX 460 2GB is superior to the Radeon HD 4870 512MB, by a large margin. (explain)

GeForce GTX 460 2GB		21600 Mpixels/sec
Radeon HD 4870 512MB		12000 Mpixels/sec
	Difference: 9600 (80%)

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 (in units of megabytes per second) that can be transported across the external memory interface in one second. It's calculated by multiplying the interface width by its memory speed. If it uses DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This number is worked out by multiplying the total number of texture units by the core speed of the chip. The higher this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly record to the local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.