GeForce GTX 560 Ti vs Radeon HD 3870 X2 1GB

Intro

Compare those specifications to the Radeon HD 3870 X2 1GB, which comes with a clock frequency of 825 MHz and a GDDR4 memory speed of 1126 MHz. It also uses a 256-bit bus, and uses a 55 nm design. It is made up of 320(64x5) SPUs, 16 Texture Address Units, and 16 Raster Operation Units.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically speaking, the Radeon HD 3870 X2 1GB should perform a bit faster than the GeForce GTX 560 Ti overall. (explain)

Radeon HD 3870 X2 1GB		144128 MB/sec
GeForce GTX 560 Ti		128256 MB/sec
	Difference: 15872 (12%)

Texel Rate

The GeForce GTX 560 Ti is quite a bit (about 99%) faster with regards to texture filtering than the Radeon HD 3870 X2 1GB. (explain)

GeForce GTX 560 Ti		52608 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 26208 (99%)

Pixel Rate

If running with a high resolution is important to you, then the Radeon HD 3870 X2 1GB is the winner, though not by far. (explain)

Radeon HD 3870 X2 1GB		26400 Mpixels/sec
GeForce GTX 560 Ti		26304 Mpixels/sec
	Difference: 96 (0%)

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.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the largest amount of information (counted in MB per second) that can be transferred over the external memory interface in a second. It is worked out by multiplying the card's bus width by its memory speed. If it uses DDR type RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, 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 per second. This figure is worked out 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 handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly write to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.