Compare any two graphics cards:
GeForce 8800 GTS (G80) 640MB vs Radeon HD 4830 1GB
IntroThe GeForce 8800 GTS (G80) 640MB features clock speeds of 513 MHz on the GPU, and 792 MHz on the 640 MB of GDDR3 RAM. It features 96 SPUs along with 48 Texture Address Units and 20 Rasterization Operator Units.
Compare those specs to the Radeon HD 4830 1GB, which has core clock speeds of 575 MHz on the GPU, and 900 MHz on the 1024 MB of GDDR4 memory. It features 640(128x5) SPUs along with 32 Texture Address Units and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce 8800 GTS (G80) 640MB will be 10% quicker than the Radeon HD 4830 1GB in general, because of its greater bandwidth. (explain)
Texel RateThe GeForce 8800 GTS (G80) 640MB is a lot (about 34%) better at texture filtering than the Radeon HD 4830 1GB. (explain)
Pixel RateThe GeForce 8800 GTS (G80) 640MB should be a small bit (approximately 12%) more effective at anti-aliasing than the Radeon HD 4830 1GB, and also will be capable of handling higher 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: Memory bandwidth is the max amount of data (measured in megabytes per second) that can be moved past the external memory interface within a second. The number is worked out by multiplying the bus width by its memory speed. In the case of DDR RAM, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total texture units by the core speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly record to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends 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.