Compare any two graphics cards:
Radeon HD 4650 512MB vs Radeon HD 7750
IntroThe Radeon HD 4650 512MB makes use of a 55 nm design. AMD has set the core speed at 600 MHz. The DDR2 RAM runs at a speed of 500 MHz on this specific card. It features 320(64x5) SPUs along with 32 TAUs and 8 ROPs.
Compare those specifications to the Radeon HD 7750, which makes use of a 28 nm design. AMD has clocked the core frequency at 800 MHz. The GDDR5 RAM works at a speed of 1125 MHz on this particular card. It features 512 SPUs as well as 32 TAUs and 16 Rasterization Operator Units.
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
Theoretically speaking, the Radeon HD 7750 should be 350% faster than the Radeon HD 4650 512MB in general, due to its higher bandwidth. (explain)
Texel RateThe Radeon HD 7750 is a lot (more or less 33%) more effective at texture filtering than the Radeon HD 4650 512MB. (explain)
Pixel RateThe Radeon HD 7750 should be much (about 167%) better at FSAA than the Radeon HD 4650 512MB, and also will be able to handle higher resolutions while still performing well. (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 max amount of data (in units of megabytes per second) that can be transferred across the external memory interface in one second. It's worked out by multiplying the bus width by the speed of its memory. In the case of DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed per second. This number is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The higher the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the most 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 Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called 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 - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.