Compare any two graphics cards:
Radeon HD 4650 1GB vs Radeon HD 7750
IntroThe Radeon HD 4650 1GB makes use of a 55 nm design. AMD has clocked the core frequency at 600 MHz. The GDDR3 RAM runs at a speed of 700 MHz on this particular card. It features 320(64x5) SPUs as well as 32 Texture Address Units and 8 ROPs.
Compare those specifications to the Radeon HD 7750, which comes with GPU clock speed of 800 MHz, and 1024 MB of GDDR5 memory set to run at 1125 MHz through a 128-bit bus. It also is made up of 512 SPUs, 32 Texture Address Units, and 16 Raster Operation Units.
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
The Radeon HD 7750 should in theory perform much faster than the Radeon HD 4650 1GB overall. (explain)
Texel RateThe Radeon HD 7750 should be much (more or less 33%) better at texture filtering than the Radeon HD 4650 1GB. (explain)
Pixel RateThe Radeon HD 7750 will be quite a bit (more or less 167%) more effective at anti-aliasing than the Radeon HD 4650 1GB, and also will be capable of handling higher screen 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: Bandwidth is the largest amount of data (in units of MB per second) that can be transferred over the external memory interface in one second. The number is calculated by multiplying the bus width by its memory speed. If the card has DDR type memory, it must be multiplied by 2 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 AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed in one second. This figure is worked out by multiplying the total texture units by the core clock speed of the chip. The higher the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the maximum number of pixels the video card can possibly write to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the number of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.