Compare any two graphics cards:
Radeon HD 3870 512MB vs Radeon HD 6670 (OEM) 1GB
IntroThe Radeon HD 3870 512MB uses a 55 nm design. AMD has clocked the core frequency at 775 MHz. The GDDR3 memory is set to run at a frequency of 900 MHz on this specific card. It features 320(64x5) SPUs along with 16 Texture Address Units and 16 ROPs.
Compare all that to the Radeon HD 6670 (OEM) 1GB, which has a GPU core clock speed of 800 MHz, and 1024 MB of GDDR5 memory running at 1000 MHz through a 128-bit bus. It also is made up of 480 SPUs, 24 Texture Address Units, and 8 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 6670 (OEM) 1GB should in theory perform a little bit faster than the Radeon HD 3870 512MB overall. (explain)
Texel RateThe Radeon HD 6670 (OEM) 1GB will be quite a bit (about 55%) more effective at AF 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 a better choice, and very much so. (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: Bandwidth is the maximum amount of data (measured in MB per second) that can be transferred across the external memory interface in a second. It's worked out by multiplying the interface width by the speed of its memory. If it uses DDR RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This number is calculated by multiplying the total number of texture units of the card by the core speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the most pixels the graphics card could possibly write 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 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 many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.