Compare any two graphics cards:
Radeon HD 4670 1GB vs Radeon HD 7770
IntroThe Radeon HD 4670 1GB comes with a clock speed of 750 MHz and a GDDR4/GDDR3/DDR3/DDR2 memory speed of 1100 MHz. It also features a 128-bit memory bus, and uses a 55 nm design. It is comprised of 320(64x5) SPUs, 32 TAUs, and 8 Raster Operation Units.
Compare those specs to the Radeon HD 7770, which comes with a core clock speed of 1000 MHz and a GDDR5 memory frequency of 1125 MHz. It also uses a 128-bit memory bus, and uses a 28 nm design. It features 640 SPUs, 40 Texture Address Units, and 16 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 7770 should theoretically be a lot better than the Radeon HD 4670 1GB in general. (explain)
Texel RateThe Radeon HD 7770 should be quite a bit (about 67%) more effective at texture filtering than the Radeon HD 4670 1GB. (explain)
Pixel RateIf running with high levels of AA is important to you, then the Radeon HD 7770 is the winner, and very much so. (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 maximum amount of information (counted in MB per second) that can be transported over the external memory interface in a second. The number is worked out by multiplying the bus width by the speed of its memory. In the case of DDR type RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one second. This is calculated by multiplying the total texture units by the core speed of the chip. The higher this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to the local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the the core speed of the card. 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, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.