Compare any two graphics cards:
Radeon HD 7870 vs Radeon HD 7950
IntroThe Radeon HD 7870 has a GPU clock speed of 1000 MHz, and the 2048 MB of GDDR5 RAM runs at 1200 MHz through a 256-bit bus. It also features 1280 SPUs, 80 Texture Address Units, and 32 ROPs.
Compare all that to the Radeon HD 7950, which comes with core speeds of 800 MHz on the GPU, and 1250 MHz on the 1536 MB of GDDR5 memory. It features 1792 SPUs as well as 112 Texture Address Units and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7950 should be 56% quicker than the Radeon HD 7870 in general, due to its higher bandwidth. (explain)
Texel RateThe Radeon HD 7950 will be a little bit (approximately 12%) better at AF than the Radeon HD 7870. (explain)
Pixel RateThe Radeon HD 7870 will be much (more or less 25%) better at FSAA than the Radeon HD 7950, and also should be capable of handling higher resolutions more effectively. (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 (measured in MB per second) that can be transferred past the external memory interface within a second. The number is worked out by multiplying the card's interface width by its memory speed. In the case of DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This number is worked out by multiplying the total texture units of the card by the core speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly write to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Render Output Units by the clock 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 rate also depends on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.