Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 7950
IntroThe Radeon HD 5870 features core speeds of 850 MHz on the GPU, and 1200 MHz on the 1024 MB of GDDR5 memory. It features 1600(320x5) SPUs as well as 80 Texture Address Units and 32 Rasterization Operator Units.
Compare those specifications to the Radeon HD 7950, which has core clock speeds of 800 MHz on the GPU, and 1250 MHz on the 1536 MB of GDDR5 memory. It features 1792 SPUs along with 112 Texture Address Units and 32 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7950, in theory, should be much faster than the Radeon HD 5870 overall. (explain)
Texel RateThe Radeon HD 7950 will be much (about 32%) better at AF than the Radeon HD 5870. (explain)
Pixel RateIf using a high resolution is important to you, then the Radeon HD 5870 is the winner, though only just barely. (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 transported over the external memory interface within a second. It is worked out by multiplying the card's interface width by the speed of its memory. In the case of DDR type memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied per second. This is calculated by multiplying the total number of texture units of the card 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 one second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly record to the local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.