Compare any two graphics cards:
GeForce 8800 GTS (G80) 640MB vs Radeon HD 4650 1GB
IntroThe GeForce 8800 GTS (G80) 640MB makes use of a 90 nm design. nVidia has set the core frequency at 513 MHz. The GDDR3 RAM is set to run at a speed of 792 MHz on this particular model. It features 96 SPUs as well as 48 TAUs and 20 ROPs.
Compare all of that to the Radeon HD 4650 1GB, which makes use of a 55 nm design. AMD has set the core frequency at 600 MHz. The GDDR3 RAM is set to run at a frequency of 700 MHz on this specific model. It features 320(64x5) SPUs as well as 32 TAUs and 8 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the GeForce 8800 GTS (G80) 640MB should in theory be much better than the Radeon HD 4650 1GB overall. (explain)
Texel RateThe GeForce 8800 GTS (G80) 640MB is a lot (approximately 28%) more effective at AF than the Radeon HD 4650 1GB. (explain)
Pixel RateThe GeForce 8800 GTS (G80) 640MB should be quite a bit (about 114%) faster with regards to FSAA than the Radeon HD 4650 1GB, and also able to handle higher resolutions better. (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 information (in units of MB per second) that can be transferred past the external memory interface in one second. It's worked out by multiplying the card's interface width by the speed of its memory. If it uses DDR type RAM, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the 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 number of texture map elements (texels) that are processed in one second. This is worked out by multiplying the total texture units of the card by the core clock speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.