Compare any two graphics cards:
GeForce 8800 GTS (G80) 640MB vs Radeon HD 4650 1GB
IntroThe GeForce 8800 GTS (G80) 640MB comes with a clock speed of 513 MHz and a GDDR3 memory speed of 792 MHz. It also makes use of a 320-bit memory bus, and uses a 90 nm design. It features 96 SPUs, 48 TAUs, and 20 ROPs.
Compare all that to the Radeon HD 4650 1GB, which features core speeds of 600 MHz on the GPU, and 700 MHz on the 1024 MB of GDDR3 memory. It features 320(64x5) SPUs along with 32 TAUs and 8 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce 8800 GTS (G80) 640MB, in theory, should be quite a bit faster than the Radeon HD 4650 1GB overall. (explain)
Texel RateThe GeForce 8800 GTS (G80) 640MB will be a lot (approximately 28%) faster with regards to anisotropic filtering than the Radeon HD 4650 1GB. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the GeForce 8800 GTS (G80) 640MB is superior to the Radeon HD 4650 1GB, and very much so. (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 maximum amount of data (counted in MB per second) that can be moved over the external memory interface within a second. The number is calculated by multiplying the interface width by its memory speed. If the card has DDR type RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied in one second. This figure is worked out by multiplying the total number of texture units by the core clock speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip can possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as 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, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.