Compare any two graphics cards:
Radeon HD 4650 1GB vs Radeon HD 7750
IntroThe Radeon HD 4650 1GB features a GPU core clock speed of 600 MHz, and the 1024 MB of GDDR3 RAM is set to run at 700 MHz through a 128-bit bus. It also is made up of 320(64x5) Stream Processors, 32 Texture Address Units, and 8 Raster Operation Units.
Compare all that to the Radeon HD 7750, which features a core clock speed of 800 MHz and a GDDR5 memory speed of 1125 MHz. It also uses a 128-bit memory bus, and makes use of a 28 nm design. It is made up of 512 SPUs, 32 Texture Address Units, and 16 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
As far as performance goes, the Radeon HD 7750 should in theory be a lot superior to the Radeon HD 4650 1GB in general. (explain)
Texel RateThe Radeon HD 7750 will be a lot (more or less 33%) faster with regards to AF than the Radeon HD 4650 1GB. (explain)
Pixel RateIf using a high resolution is important to you, then the Radeon HD 7750 is the winner, 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: Memory bandwidth is the largest amount of data (counted in megabytes per second) that can be transported across the external memory interface in one second. It is worked out by multiplying the card's interface width by its memory speed. In the case of DDR RAM, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the faster 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 amount of texture map elements (texels) that are applied per second. This is calculated by multiplying the total amount of texture units by the core clock speed of the chip. The better this number, the better the video card will be at handling 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 record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.