Compare any two graphics cards:
GeForce GTX 650 vs Radeon HD 6870
IntroThe GeForce GTX 650 has a GPU clock speed of 1058 MHz, and the 2048 MB of GDDR5 memory is set to run at 1250 MHz through a 128-bit bus. It also is made up of 384 SPUs, 32 TAUs, and 16 Raster Operation Units.
Compare all that to the Radeon HD 6870, which has a GPU core clock speed of 900 MHz, and 1024 MB of GDDR5 memory running at 1050 MHz through a 256-bit bus. It also features 1120 SPUs, 56 TAUs, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 6870 should perform a lot faster than the GeForce GTX 650 overall. (explain)
Texel RateThe Radeon HD 6870 is quite a bit (more or less 49%) faster with regards to texture filtering than the GeForce GTX 650. (explain)
Pixel RateThe Radeon HD 6870 should be a lot (more or less 70%) faster with regards to AA 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 max amount of information (in units of MB per second) that can be transported over the external memory interface in a second. It is calculated by multiplying the card's bus width by its memory speed. If the card has DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This number is calculated by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the most pixels the graphics card could possibly write to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Render Output Units by the clock speed of the card. 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 fill rate also depends on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.