Compare any two graphics cards:
GeForce GTX 650 vs Radeon HD 6870
IntroThe GeForce GTX 650 makes use of a 28 nm design. nVidia has clocked the core speed at 1058 MHz. The GDDR5 RAM runs at a speed of 1250 MHz on this particular card. It features 384 SPUs as well as 32 Texture Address Units and 16 ROPs.
Compare all of that to the Radeon HD 6870, which features a clock frequency of 900 MHz and a GDDR5 memory frequency of 1050 MHz. It also features a 256-bit bus, and makes use of a 40 nm design. It is comprised of 1120 SPUs, 56 TAUs, and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 6870 should perform much faster than the GeForce GTX 650 overall. (explain)
Texel RateThe Radeon HD 6870 is a lot (approximately 49%) more effective at AF than the GeForce GTX 650. (explain)
Pixel RateThe Radeon HD 6870 should be a lot (more or less 70%) more effective at FSAA than the GeForce GTX 650, and capable of handling 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 megabytes per second) that can be transferred across the external memory interface in one second. It's worked out by multiplying the interface width by its memory clock speed. If the card has DDR RAM, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This figure is worked out by multiplying the total texture units by the core clock speed of the chip. The better this number, 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 that the graphics card can possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.