Compare any two graphics cards:
Geforce GTX 680 vs Radeon HD 4850 1GB
IntroThe Geforce GTX 680 comes with core speeds of 1006 MHz on the GPU, and 1502 MHz on the 2048 MB of GDDR5 memory. It features 1536 SPUs along with 128 Texture Address Units and 32 ROPs.
Compare those specifications to the Radeon HD 4850 1GB, which has core clock speeds of 625 MHz on the GPU, and 993 MHz on the 1024 MB of GDDR4 RAM. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Geforce GTX 680 should in theory be much better than the Radeon HD 4850 1GB in general. (explain)
Texel RateThe Geforce GTX 680 should be a lot (more or less 415%) better at AF than the Radeon HD 4850 1GB. (explain)
Pixel RateThe Geforce GTX 680 is quite a bit (about 222%) more effective at anti-aliasing than the Radeon HD 4850 1GB, and able to handle higher screen 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: Memory bandwidth is the maximum amount of information (in units of MB per second) that can be transported over the external memory interface in a second. It's worked out by multiplying the card's bus width by the speed of its memory. In the case of DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip can possibly write to its local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Render Output Units by the the card's clock speed. 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 also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.