Compare any two graphics cards:
Radeon HD 4730 vs Radeon HD 4770
IntroThe Radeon HD 4730 has core speeds of 700 MHz on the GPU, and 900 MHz on the 512 MB of GDDR5 RAM. It features 640(128x5) SPUs as well as 32 TAUs and 8 ROPs.
Compare those specs to the Radeon HD 4770, which comes with a GPU core clock speed of 750 MHz, and 512 MB of GDDR5 memory running at 800 MHz through a 128-bit bus. It also is comprised of 640(128x5) SPUs, 32 TAUs, and 16 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 4730 should be 13% quicker than the Radeon HD 4770 overall, due to its higher data rate. (explain)
Texel RateThe Radeon HD 4770 should be just a bit (about 7%) more effective at AF than the Radeon HD 4730. (explain)
Pixel RateIf running with a high resolution is important to you, then the Radeon HD 4770 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 largest amount of data (in units of megabytes per second) that can be moved over the external memory interface in a second. It's calculated by multiplying the card's bus width by its memory speed. If it uses DDR memory, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's 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 amount of texture map elements (texels) that are applied per second. This figure is calculated by multiplying the total texture units of the card by the core speed of the chip. The higher the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly write to its local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as 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, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.