Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 7950
IntroThe Radeon HD 5870 has core speeds of 850 MHz on the GPU, and 1200 MHz on the 1024 MB of GDDR5 RAM. It features 1600(320x5) SPUs as well as 80 TAUs and 32 ROPs.
Compare all that to the Radeon HD 7950, which makes use of a 28 nm design. AMD has set the core frequency at 800 MHz. The GDDR5 memory works at a frequency of 1250 MHz on this particular card. It features 1792 SPUs along with 112 Texture Address Units and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7950 should perform a lot faster than the Radeon HD 5870 in general. (explain)
Texel RateThe Radeon HD 7950 is much (more or less 32%) more effective at anisotropic filtering than the Radeon HD 5870. (explain)
Pixel RateIf running with a high screen resolution is important to you, then the Radeon HD 5870 is the winner, but not by far. (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 largest amount of data (in units of megabytes per second) that can be transported across the external memory interface in a second. The number is worked out by multiplying the bus width by its memory speed. If it uses DDR type memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This number is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The higher 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 maximum number of pixels the video card can possibly write to its local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate is also dependant on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.