Compare any two graphics cards:
GeForce 8800 GTS (G80) 640MB vs Radeon HD 4650 1GB
IntroThe GeForce 8800 GTS (G80) 640MB features a GPU core 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 features 96 SPUs, 48 TAUs, and 20 Raster Operation Units.
Compare those specs to the Radeon HD 4650 1GB, which features core clock speeds of 600 MHz on the GPU, and 700 MHz on the 1024 MB of GDDR3 memory. It features 320(64x5) SPUs as well as 32 Texture Address Units and 8 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce 8800 GTS (G80) 640MB should theoretically be much faster than the Radeon HD 4650 1GB in general. (explain)
Texel RateThe GeForce 8800 GTS (G80) 640MB will be much (approximately 28%) more effective at anisotropic filtering than the Radeon HD 4650 1GB. (explain)
Pixel RateThe GeForce 8800 GTS (G80) 640MB is a lot (about 114%) faster with regards to AA than the Radeon HD 4650 1GB, and should be able to handle higher screen resolutions without slowing down too much. (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 (in units of megabytes per second) that can be moved across the external memory interface within a second. It is calculated by multiplying the card's bus width by its memory speed. If it uses DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed per second. This number is calculated by multiplying the total number of texture units of the card by the core clock speed of the chip. The better the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly record to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.