Compare any two graphics cards:
Radeon HD 3870 512MB vs Radeon HD 6670 (OEM) 1GB
IntroThe Radeon HD 3870 512MB features a GPU clock speed of 775 MHz, and the 512 MB of GDDR3 memory runs at 900 MHz through a 256-bit bus. It also features 320(64x5) Stream Processors, 16 TAUs, and 16 Raster Operation Units.
Compare all that to the Radeon HD 6670 (OEM) 1GB, which has core speeds of 800 MHz on the GPU, and 1000 MHz on the 1024 MB of GDDR5 memory. It features 480 SPUs along with 24 Texture Address Units and 8 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 6670 (OEM) 1GB should in theory perform just a bit faster than the Radeon HD 3870 512MB overall. (explain)
Texel RateThe Radeon HD 6670 (OEM) 1GB is much (more or less 55%) more effective at texture filtering than the Radeon HD 3870 512MB. (explain)
Pixel RateThe Radeon HD 3870 512MB is much (more or less 94%) faster with regards to anti-aliasing than the Radeon HD 6670 (OEM) 1GB, and able to handle higher 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 data (in units of MB per second) that can be transferred across the external memory interface in a second. The number is calculated by multiplying the card's bus width by its memory clock speed. If it uses DDR memory, the result should be multiplied by 2 once again. If 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 texture map elements (texels) that are applied per second. This number is worked out by multiplying the total amount of texture units by the core speed of the chip. The better this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.