Compare any two graphics cards:
Radeon HD 4650 512MB vs Radeon HD 7750
IntroThe Radeon HD 4650 512MB has clock speeds of 600 MHz on the GPU, and 500 MHz on the 512 MB of DDR2 memory. It features 320(64x5) SPUs as well as 32 TAUs and 8 Rasterization Operator Units.
Compare all of that to the Radeon HD 7750, which has a core clock speed of 800 MHz and a GDDR5 memory frequency of 1125 MHz. It also features a 128-bit bus, and makes use of a 28 nm design. It is comprised of 512 SPUs, 32 Texture Address Units, and 16 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
Theoretically, the Radeon HD 7750 should perform quite a bit faster than the Radeon HD 4650 512MB overall. (explain)
Texel RateThe Radeon HD 7750 will be much (about 33%) better at texture filtering than the Radeon HD 4650 512MB. (explain)
Pixel RateThe Radeon HD 7750 is much (more or less 167%) faster with regards to anti-aliasing than the Radeon HD 4650 512MB, and also will be able to handle higher screen resolutions without slowing down too much. (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 largest amount of data (counted in MB per second) that can be transported over the external memory interface in one second. The number is worked out by multiplying the bus width by its memory clock speed. If the card has DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This is worked out by multiplying the total number of texture units by the core clock speed of the chip. The higher 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 could possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.