Compare any two graphics cards:
GeForce 8800 GTS (G80) 640MB vs Radeon HD 4650 1GB
IntroThe GeForce 8800 GTS (G80) 640MB comes with a core clock frequency of 513 MHz and a GDDR3 memory frequency of 792 MHz. It also makes use of a 320-bit bus, and makes use of a 90 nm design. It is comprised of 96 SPUs, 48 Texture Address Units, and 20 ROPs.
Compare those specs to the Radeon HD 4650 1GB, which comes with a clock speed of 600 MHz and a GDDR3 memory frequency of 700 MHz. It also makes use of a 128-bit memory bus, and uses a 55 nm design. It is comprised of 320(64x5) SPUs, 32 Texture Address Units, and 8 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the GeForce 8800 GTS (G80) 640MB should be quite a bit faster than the Radeon HD 4650 1GB overall. (explain)
Texel RateThe GeForce 8800 GTS (G80) 640MB will be quite a bit (about 28%) faster with regards to texture filtering than the Radeon HD 4650 1GB. (explain)
Pixel RateThe GeForce 8800 GTS (G80) 640MB will be much (approximately 114%) faster with regards to anti-aliasing than the Radeon HD 4650 1GB, and also should be able to handle higher 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 max amount of information (measured in MB per second) that can be transferred over the external memory interface within a second. It is calculated by multiplying the card's interface width by the speed of its memory. If it uses DDR RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster 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 are processed in one second. This number is worked out by multiplying the total number of texture units by the core speed of the chip. The higher this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Raster Operations Pipelines 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 fill rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.