Compare any two graphics cards:
Radeon HD 7770 vs Radeon HD 7870
IntroThe Radeon HD 7770 features core clock speeds of 1000 MHz on the GPU, and 1125 MHz on the 1024 MB of GDDR5 RAM. It features 640 SPUs as well as 40 TAUs and 16 Rasterization Operator Units.
Compare all of that to the Radeon HD 7870, which uses a 28 nm design. AMD has set the core speed at 1000 MHz. The GDDR5 memory works at a frequency of 1200 MHz on this specific card. It features 1280 SPUs along with 80 Texture Address Units and 32 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 7870 should theoretically be a lot superior to the Radeon HD 7770 in general. (explain)
Texel RateThe Radeon HD 7870 should be much (more or less 100%) faster with regards to anisotropic filtering than the Radeon HD 7770. (explain)
Pixel RateThe Radeon HD 7870 is a lot (about 100%) better at AA than the Radeon HD 7770, and also should be able to handle higher screen resolutions while still performing well. (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 maximum amount of information (counted in MB per second) that can be transferred past the external memory interface in a second. It is calculated by multiplying the interface width by its memory clock speed. In the case of DDR type memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This number is calculated by multiplying the total texture units by the core clock speed of the chip. The better this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly record to its local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the number of colour ROPs by the the card's 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 output rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.