Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 7850
IntroThe Radeon HD 5870 has a GPU core clock speed of 850 MHz, and the 1024 MB of GDDR5 memory is set to run at 1200 MHz through a 256-bit bus. It also is comprised of 1600(320x5) Stream Processors, 80 TAUs, and 32 ROPs.
Compare those specifications to the Radeon HD 7850, which makes use of a 28 nm design. AMD has clocked the core speed at 860 MHz. The GDDR5 memory works at a speed of 1200 MHz on this card. It features 1024 SPUs as well as 64 TAUs and 32 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same memory bandwidth, so theoretically they should perform the same. (explain)
Texel RateThe Radeon HD 5870 will be a lot (more or less 24%) more effective at AF than the Radeon HD 7850. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon HD 7850 is superior to the Radeon HD 5870, but only just. (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 moved across the external memory interface in one second. It's calculated by multiplying the bus width by the speed of its memory. In the case of DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the faster the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed 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 better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.