Compare any two graphics cards:
Radeon HD 4870 1GB vs Radeon HD 6670 (OEM)
IntroThe Radeon HD 4870 1GB comes with clock speeds of 750 MHz on the GPU, and 900 MHz on the 1024 MB of GDDR5 memory. It features 800(160x5) SPUs as well as 40 Texture Address Units and 16 Rasterization Operator Units.
Compare all of that to the Radeon HD 6670 (OEM), which comes with core clock speeds of 800 MHz on the GPU, and 1000 MHz on the 512 MB of GDDR5 memory. It features 480 SPUs along with 24 TAUs and 8 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 4870 1GB will be 80% quicker than the Radeon HD 6670 (OEM) in general, because of its higher bandwidth. (explain)
Texel RateThe Radeon HD 4870 1GB is much (about 56%) better at AF than the Radeon HD 6670 (OEM). (explain)
Pixel RateThe Radeon HD 4870 1GB is quite a bit (about 88%) better at FSAA than the Radeon HD 6670 (OEM), and will be 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 largest amount of data (in units of megabytes per second) that can be transported past the external memory interface in one second. It's calculated by multiplying the interface width by its memory speed. If it uses DDR RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This is worked out by multiplying the total texture units of the card by the core speed of the chip. The better the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly write to its local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.