Compare any two graphics cards:
Radeon HD 5770 vs Radeon HD 5870
IntroThe Radeon HD 5770 comes with a clock frequency of 850 MHz and a GDDR5 memory frequency of 1200 MHz. It also makes use of a 128-bit bus, and makes use of a 40 nm design. It is comprised of 800(160x5) SPUs, 40 TAUs, and 16 ROPs.
Compare all that to the Radeon HD 5870, which comes with a clock frequency of 850 MHz and a GDDR5 memory frequency of 1200 MHz. It also features a 256-bit memory bus, and uses a 40 nm design. It features 1600(320x5) SPUs, 80 TAUs, and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 5870 should perform much faster than the Radeon HD 5770 overall. (explain)
Texel RateThe Radeon HD 5870 is quite a bit (approximately 100%) faster with regards to AF than the Radeon HD 5770. (explain)
Pixel RateThe Radeon HD 5870 should be much (approximately 100%) faster with regards to anti-aliasing than the Radeon HD 5770, and also will be capable of handling higher 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 largest amount of information (measured in megabytes per second) that can be transferred past the external memory interface in a second. The number is calculated by multiplying the card's bus width by the speed of its memory. If the card has DDR RAM, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed per second. This is worked out by multiplying the total number of texture units by the core speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly record to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.