Compare any two graphics cards:
Radeon HD 7870 vs Radeon HD 7950 3GB
IntroThe Radeon HD 7870 makes use of a 28 nm design. AMD has set the core speed at 1000 MHz. The GDDR5 memory works at a speed of 1200 MHz on this card. It features 1280 SPUs along with 80 Texture Address Units and 32 ROPs.
Compare those specifications to the Radeon HD 7950 3GB, which comes with clock speeds of 800 MHz on the GPU, and 1250 MHz on the 3072 MB of GDDR5 RAM. It features 1792 SPUs along with 112 TAUs and 32 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7950 3GB should be quite a bit faster than the Radeon HD 7870 in general. (explain)
Texel RateThe Radeon HD 7950 3GB will be just a bit (about 12%) faster with regards to anisotropic filtering than the Radeon HD 7870. (explain)
Pixel RateIf running with a high screen resolution is important to you, then the Radeon HD 7870 is a better choice, by a large margin. (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 (counted in MB per second) that can be transported across the external memory interface within a second. It is worked out by multiplying the card's interface width by its memory speed. If the card has DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the faster 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 applied in one second. This is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The better the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.