Compare any two graphics cards:
GeForce GTX 280 vs Radeon HD 7950
IntroThe GeForce GTX 280 comes with a GPU core clock speed of 602 MHz, and the 1024 MB of GDDR3 memory runs at 1107 MHz through a 512-bit bus. It also is comprised of 240 Stream Processors, 80 Texture Address Units, and 32 ROPs.
Compare all that to the Radeon HD 7950, which comes with a core clock frequency of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also uses a 384-bit bus, and makes use of a 28 nm design. It features 1792 SPUs, 112 TAUs, and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7950 should theoretically be quite a bit faster than the GeForce GTX 280 overall. (explain)
Texel RateThe Radeon HD 7950 will be a lot (about 86%) more effective at texture filtering than the GeForce GTX 280. (explain)
Pixel RateThe Radeon HD 7950 is quite a bit (approximately 33%) faster with regards to full screen anti-aliasing than the GeForce GTX 280, and also should be capable of handling higher screen resolutions without slowing down too much. (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: Bandwidth is the max amount of data (in units of MB per second) that can be moved past the external memory interface in a second. It is calculated by multiplying the interface width by its memory speed. If the card has DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed in one second. This is calculated by multiplying the total number of texture units by the core clock 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 in a second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly record to its local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.