Compare any two graphics cards:
Radeon HD 4670 1GB vs Radeon HD 7770
IntroThe Radeon HD 4670 1GB has a GPU core speed of 750 MHz, and the 1024 MB of GDDR4/GDDR3/DDR3/DDR2 memory is set to run at 1100 MHz through a 128-bit bus. It also is comprised of 320(64x5) SPUs, 32 TAUs, and 8 ROPs.
Compare all of that to the Radeon HD 7770, which has a core clock speed of 1000 MHz and a GDDR5 memory speed of 1125 MHz. It also makes use of a 128-bit bus, and makes use of a 28 nm design. It is made up of 640 SPUs, 40 TAUs, and 16 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the Radeon HD 7770 should be much faster than the Radeon HD 4670 1GB in general. (explain)
Texel RateThe Radeon HD 7770 should be much (about 67%) better at texture filtering than the Radeon HD 4670 1GB. (explain)
Pixel RateIf running with a high screen resolution is important to you, then the Radeon HD 7770 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: Bandwidth is the maximum amount of information (counted in megabytes per second) that can be transferred past the external memory interface in a second. The number is calculated by multiplying the interface width by its memory clock speed. If it uses DDR type RAM, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better 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 are applied in one second. This number is worked out by multiplying the total amount of texture units of the card by the core 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 in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly write to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.