Compare any two graphics cards:
Radeon HD 4650 512MB vs Radeon HD 7750
IntroThe Radeon HD 4650 512MB has a clock frequency of 600 MHz and a DDR2 memory speed of 500 MHz. It also makes use of a 128-bit bus, and makes use of a 55 nm design. It is comprised of 320(64x5) SPUs, 32 Texture Address Units, and 8 Raster Operation Units.
Compare those specs to the Radeon HD 7750, which has a clock frequency of 800 MHz and a GDDR5 memory frequency of 1125 MHz. It also uses a 128-bit bus, and makes use of a 28 nm design. It is made up of 512 SPUs, 32 TAUs, and 16 ROPs.
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
As far as performance goes, the Radeon HD 7750 should in theory be quite a bit better than the Radeon HD 4650 512MB in general. (explain)
Texel RateThe Radeon HD 7750 will be quite a bit (more or less 33%) more effective at AF than the Radeon HD 4650 512MB. (explain)
Pixel RateIf running with a high resolution is important to you, then the Radeon HD 7750 is superior to the Radeon HD 4650 512MB, by a large margin. (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 max amount of data (counted in MB per second) that can be transferred past the external memory interface in a second. It's calculated by multiplying the card's interface width by its memory clock speed. If it uses DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied per second. This figure is calculated by multiplying the total number of texture units by the core clock speed of the chip. The higher this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.