GeForce GTX 285 2GB vs Radeon HD 6870

Intro

Compare that to the Radeon HD 6870, which uses a 40 nm design. ATi has clocked the core frequency at 900 MHz. The GDDR5 memory runs at a frequency of 1050 MHz on this particular card. It features 1120 SPUs along with 56 Texture Address Units and 32 ROPs.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6870		151 Watts
GeForce GTX 285 2GB		204 Watts
	Difference: 53 Watts (35%)

Memory Bandwidth

Theoretically speaking, the GeForce GTX 285 2GB should be just a bit faster than the Radeon HD 6870 in general. (explain)

GeForce GTX 285 2GB		158976 MB/sec
Radeon HD 6870		134400 MB/sec
	Difference: 24576 (18%)

Texel Rate

The GeForce GTX 285 2GB will be a little bit (more or less 3%) faster with regards to texture filtering than the Radeon HD 6870. (explain)

GeForce GTX 285 2GB		51840 Mtexels/sec
Radeon HD 6870		50400 Mtexels/sec
	Difference: 1440 (3%)

Pixel Rate

The Radeon HD 6870 should be much (more or less 39%) faster with regards to FSAA than the GeForce GTX 285 2GB, and capable of handling higher screen resolutions without slowing down too much. (explain)

Radeon HD 6870		28800 Mpixels/sec
GeForce GTX 285 2GB		20736 Mpixels/sec
	Difference: 8064 (39%)

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: Memory bandwidth is the largest amount of data (in units of megabytes per second) that can be transferred across the external memory interface in one second. It's worked out by multiplying the card's interface width by its memory clock speed. If it uses DDR memory, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip 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 amount of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.