Compare any two graphics cards:
Radeon HD 4670 1GB vs Radeon HD 7770
IntroThe Radeon HD 4670 1GB features a core clock frequency of 750 MHz and a GDDR4/GDDR3/DDR3/DDR2 memory speed of 1100 MHz. It also features a 128-bit bus, and makes use of a 55 nm design. It features 320(64x5) SPUs, 32 Texture Address Units, and 8 ROPs.
Compare that to the Radeon HD 7770, which uses a 28 nm design. AMD has set the core speed at 1000 MHz. The GDDR5 memory is set to run at a speed of 1125 MHz on this card. It features 640 SPUs as well as 40 TAUs and 16 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 7770 should be quite a bit faster than the Radeon HD 4670 1GB overall. (explain)
Texel RateThe Radeon HD 7770 should be quite a bit (more or less 67%) better at AF than the Radeon HD 4670 1GB. (explain)
Pixel RateThe Radeon HD 7770 is a lot (more or less 167%) better at full screen anti-aliasing than the Radeon HD 4670 1GB, and also should 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 (in units of MB per second) that can be moved over the external memory interface in one second. It's worked out by multiplying the interface width by its memory speed. In the case of DDR RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied in one second. This is worked out by multiplying the total texture units by the core speed of the chip. The better this number, the better the graphics 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 could possibly write to its local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of colour 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 output rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.