Compare any two graphics cards:
GeForce 8800 GTS (G80) 640MB vs Radeon HD 4650 1GB
IntroThe GeForce 8800 GTS (G80) 640MB has a GPU clock speed of 513 MHz, and the 640 MB of GDDR3 memory is set to run at 792 MHz through a 320-bit bus. It also is comprised of 96 Stream Processors, 48 Texture Address Units, and 20 ROPs.
Compare those specs to the Radeon HD 4650 1GB, which has a core clock speed of 600 MHz and a GDDR3 memory speed of 700 MHz. It also features a 128-bit bus, and makes use of a 55 nm design. It features 320(64x5) SPUs, 32 TAUs, and 8 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce 8800 GTS (G80) 640MB should in theory perform quite a bit faster than the Radeon HD 4650 1GB overall. (explain)
Texel RateThe GeForce 8800 GTS (G80) 640MB should be a lot (approximately 28%) more effective at texture filtering than the Radeon HD 4650 1GB. (explain)
Pixel RateThe GeForce 8800 GTS (G80) 640MB should be much (approximately 114%) more effective at full screen anti-aliasing than the Radeon HD 4650 1GB, and able to handle 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 (counted in MB per second) that can be transferred over the external memory interface within a second. It is calculated by multiplying the interface width by its memory clock speed. In the case of DDR type RAM, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The better this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip can possibly record to its local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.