Compare any two graphics cards:
Radeon HD 4650 1GB vs Radeon HD 7750
IntroThe Radeon HD 4650 1GB has a core clock speed of 600 MHz and a GDDR3 memory speed of 700 MHz. It also uses a 128-bit memory bus, and makes use of a 55 nm design. It features 320(64x5) SPUs, 32 TAUs, and 8 Raster Operation Units.
Compare that to the Radeon HD 7750, which comes with a clock speed of 800 MHz and a GDDR5 memory frequency of 1125 MHz. It also features a 128-bit memory bus, and makes use of a 28 nm design. It features 512 SPUs, 32 TAUs, and 16 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
The Radeon HD 7750 should theoretically be a lot faster than the Radeon HD 4650 1GB overall. (explain)
Texel RateThe Radeon HD 7750 should be much (more or less 33%) better at anisotropic filtering than the Radeon HD 4650 1GB. (explain)
Pixel RateThe Radeon HD 7750 is much (more or less 167%) better at full screen anti-aliasing than the Radeon HD 4650 1GB, and will be capable of handling higher screen 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: Bandwidth is the largest amount of information (in units of MB per second) that can be moved over the external memory interface in a second. The number is worked out by multiplying the interface width by its memory clock speed. If the card has DDR memory, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one 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 this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.