Compare any two graphics cards:
Radeon HD 7870 vs Radeon HD 7950 3GB
IntroThe Radeon HD 7870 has a GPU core speed of 1000 MHz, and the 2048 MB of GDDR5 RAM runs at 1200 MHz through a 256-bit bus. It also is made up of 1280 Stream Processors, 80 TAUs, and 32 ROPs.
Compare those specs to the Radeon HD 7950 3GB, which has a core clock speed 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 is made up of 1792 SPUs, 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 3GB should in theory perform a lot faster than the Radeon HD 7870 overall. (explain)
Texel RateThe Radeon HD 7950 3GB will be a little bit (about 12%) more effective at AF than the Radeon HD 7870. (explain)
Pixel RateThe Radeon HD 7870 should be much (approximately 25%) more effective at AA than the Radeon HD 7950 3GB, and will be able to handle higher screen 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: Bandwidth is the maximum amount of information (counted in MB per second) that can be transferred past the external memory interface within a second. It's worked out by multiplying the interface width by the speed of its memory. In the case of DDR type RAM, it must be multiplied by 2 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 high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly write to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.