Compare any two graphics cards:
GeForce GTX 460 1GB vs Radeon HD 4870 2GB
IntroThe GeForce GTX 460 1GB comes with a core clock speed of 675 MHz and a GDDR5 memory speed of 900 MHz. It also features a 256-bit memory bus, and makes use of a 40 nm design. It is made up of 336 SPUs, 56 Texture Address Units, and 32 Raster Operation Units.
Compare those specs to the Radeon HD 4870 2GB, which uses a 55 nm design. AMD has set the core frequency at 750 MHz. The GDDR5 RAM works at a frequency of 900 MHz on this particular card. It features 800(160x5) SPUs as well as 40 TAUs and 16 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same bandwidth, so in theory they should have the same performance. (explain)
Texel RateThe GeForce GTX 460 1GB is quite a bit (approximately 26%) more effective at anisotropic filtering than the Radeon HD 4870 2GB. (explain)
Pixel RateIf using a high screen resolution is important to you, then the GeForce GTX 460 1GB is the winner, by far. (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 data (counted in megabytes per second) that can be moved across the external memory interface in one second. It's worked out by multiplying the card's interface width by its memory clock speed. In the case of DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher this number, the better the card will be at 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 the graphics card could possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.