Compare any two graphics cards:
GeForce GTX 280 vs Radeon HD 7950
IntroThe GeForce GTX 280 has a GPU core clock speed of 602 MHz, and the 1024 MB of GDDR3 RAM runs at 1107 MHz through a 512-bit bus. It also is comprised of 240 SPUs, 80 TAUs, and 32 ROPs.
Compare those specifications to the Radeon HD 7950, which features GPU clock speed of 800 MHz, and 1536 MB of GDDR5 RAM running at 1250 MHz through a 384-bit bus. It also is made up of 1792 Stream Processors, 112 Texture Address Units, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7950 should theoretically be a lot faster than the GeForce GTX 280 in general. (explain)
Texel RateThe Radeon HD 7950 is much (more or less 86%) faster with regards to anisotropic filtering than the GeForce GTX 280. (explain)
Pixel RateThe Radeon HD 7950 should be quite a bit (approximately 33%) faster with regards to full screen anti-aliasing than the GeForce GTX 280, and also able to handle higher resolutions better. (explain)
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.
Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.
Memory Bandwidth: Memory bandwidth is the maximum amount of information (in units of megabytes per second) that can be transferred past the external memory interface in a second. It is worked out by multiplying the card's bus width by its memory clock speed. If it uses DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This figure is worked out by multiplying the total amount of texture units by the core speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.