GeForce GTX 285 1GB vs Radeon HD 3870 X2 1GB

Intro

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

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the GeForce GTX 285 1GB should be 10% quicker than the Radeon HD 3870 X2 1GB overall, due to its greater bandwidth. (explain)

GeForce GTX 285 1GB		158976 MB/sec
Radeon HD 3870 X2 1GB		144128 MB/sec
	Difference: 14848 (10%)

Texel Rate

The GeForce GTX 285 1GB should be much (about 96%) faster with regards to AF than the Radeon HD 3870 X2 1GB. (explain)

GeForce GTX 285 1GB		51840 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 25440 (96%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 3870 X2 1GB is superior to the GeForce GTX 285 1GB, by a large margin. (explain)

Radeon HD 3870 X2 1GB		26400 Mpixels/sec
GeForce GTX 285 1GB		20736 Mpixels/sec
	Difference: 5664 (27%)

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 maximum amount of data (counted in MB per second) that can be transferred over the external memory interface in a second. It's calculated by multiplying the card's bus width by its memory speed. If it uses DDR memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied in one second. This is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The better the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the most pixels the video card can possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.