Compare any two graphics cards:
Radeon HD 7870 vs Radeon HD 7950 3GB
IntroThe Radeon HD 7870 features a GPU clock speed of 1000 MHz, and the 2048 MB of GDDR5 memory runs at 1200 MHz through a 256-bit bus. It also is made up of 1280 SPUs, 80 TAUs, and 32 ROPs.
Compare those specs to the Radeon HD 7950 3GB, which has a clock frequency of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also makes use of a 384-bit memory bus, and makes use of a 28 nm design. It features 1792 SPUs, 112 Texture Address Units, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7950 3GB should in theory be quite a bit faster than the Radeon HD 7870 in general. (explain)
Texel RateThe Radeon HD 7950 3GB is just a bit (approximately 12%) better at anisotropic filtering than the Radeon HD 7870. (explain)
Pixel RateThe Radeon HD 7870 should be a lot (about 25%) better at FSAA than the Radeon HD 7950 3GB, and also will be capable of handling higher 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 largest amount of data (counted in megabytes per second) that can be moved across the external memory interface in a second. It is calculated by multiplying the bus width by its memory speed. If it uses DDR RAM, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one second. This number is worked out by multiplying the total amount of texture units 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 in a second.
Pixel Rate: Pixel rate is the most pixels the graphics card can possibly record to its local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the number of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.