Compare any two graphics cards:
Radeon HD 4650 512MB vs Radeon HD 7750
IntroThe Radeon HD 4650 512MB has a GPU core clock speed of 600 MHz, and the 512 MB of DDR2 RAM is set to run at 500 MHz through a 128-bit bus. It also features 320(64x5) SPUs, 32 Texture Address Units, and 8 ROPs.
Compare those specs to the Radeon HD 7750, which comes with clock speeds of 800 MHz on the GPU, and 1125 MHz on the 1024 MB of GDDR5 memory. It features 512 SPUs along with 32 Texture Address Units and 16 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
Performance-wise, the Radeon HD 7750 should in theory be much better than the Radeon HD 4650 512MB in general. (explain)
Texel RateThe Radeon HD 7750 should be much (approximately 33%) faster with regards to anisotropic filtering than the Radeon HD 4650 512MB. (explain)
Pixel RateThe Radeon HD 7750 is much (approximately 167%) better at FSAA than the Radeon HD 4650 512MB, and will be capable of handling higher screen resolutions better. (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 megabytes per second) that can be transported across the external memory interface in a second. The number is calculated by multiplying the bus width by its memory clock speed. If the card has DDR type RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied per second. This figure is calculated by multiplying the total texture units by the core clock speed of the chip. The better the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly write to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.