Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 7770
IntroThe Radeon HD 5870 has a clock speed of 850 MHz and a GDDR5 memory frequency of 1200 MHz. It also makes use of a 256-bit memory bus, and uses a 40 nm design. It is comprised of 1600(320x5) SPUs, 80 Texture Address Units, and 32 Raster Operation Units.
Compare all that to the Radeon HD 7770, which has GPU core speed of 1000 MHz, and 1024 MB of GDDR5 RAM running at 1125 MHz through a 128-bit bus. It also is comprised of 640 SPUs, 40 TAUs, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 5870 should in theory be a lot superior to the Radeon HD 7770 in general. (explain)
Texel RateThe Radeon HD 5870 should be much (approximately 70%) more effective at AF than the Radeon HD 7770. (explain)
Pixel RateThe Radeon HD 5870 will be quite a bit (more or less 70%) faster with regards to FSAA than the Radeon HD 7770, and also able to handle higher screen resolutions without losing too much performance. (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 information (measured in MB per second) that can be transferred across the external memory interface within a second. It is calculated by multiplying the bus width by its memory clock speed. In the case of DDR type memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This figure is worked out by multiplying the total texture units by the core speed of the chip. The better the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip can possibly write to the local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called 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, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.