Compare any two graphics cards:
Radeon HD 7770 vs Radeon HD 7870
IntroThe Radeon HD 7770 features a GPU core clock speed of 1000 MHz, and the 1024 MB of GDDR5 RAM is set to run at 1125 MHz through a 128-bit bus. It also features 640 Stream Processors, 40 Texture Address Units, and 16 Raster Operation Units.
Compare those specifications to the Radeon HD 7870, which uses a 28 nm design. AMD has set the core speed at 1000 MHz. The GDDR5 RAM runs at a speed of 1200 MHz on this specific card. It features 1280 SPUs along with 80 TAUs and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7870 should theoretically be quite a bit faster than the Radeon HD 7770 overall. (explain)
Texel RateThe Radeon HD 7870 will be a lot (approximately 100%) better at anisotropic filtering than the Radeon HD 7770. (explain)
Pixel RateIf running with a high resolution is important to you, then the Radeon HD 7870 is the winner, 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: Memory bandwidth is the max amount of data (measured in MB per second) that can be transferred over the external memory interface in one second. It's worked out by multiplying the card's bus width by its memory clock speed. If it uses DDR type memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This figure is calculated by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better the texel rate, the better the 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 graphics card could possibly write to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as 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, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.