Compare any two graphics cards:
Radeon HD 3870 512MB vs Radeon HD 6670 (OEM) 1GB
IntroThe Radeon HD 3870 512MB comes with a core clock frequency of 775 MHz and a GDDR3 memory speed of 900 MHz. It also features a 256-bit memory bus, and makes use of a 55 nm design. It is made up of 320(64x5) SPUs, 16 TAUs, and 16 Raster Operation Units.
Compare that to the Radeon HD 6670 (OEM) 1GB, which uses a 40 nm design. AMD has set the core speed at 800 MHz. The GDDR5 RAM is set to run at a speed of 1000 MHz on this particular model. It features 480 SPUs as well as 24 Texture Address Units and 8 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Radeon HD 6670 (OEM) 1GB should in theory be a little bit better than the Radeon HD 3870 512MB in general. (explain)
Texel RateThe Radeon HD 6670 (OEM) 1GB should be quite a bit (more or less 55%) faster with regards to anisotropic filtering than the Radeon HD 3870 512MB. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the Radeon HD 3870 512MB is the winner, by a large margin. (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 megabytes per second) that can be transferred past the external memory interface in a second. It is worked out by multiplying the card's bus width by the speed of its memory. If the card has DDR RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This figure is calculated 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 video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly write to the local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.