Compare any two graphics cards:
Radeon HD 4870 1GB vs Radeon HD 6670 (OEM)
IntroThe Radeon HD 4870 1GB uses a 55 nm design. AMD has clocked the core frequency at 750 MHz. The GDDR5 RAM works at a frequency of 900 MHz on this particular model. It features 800(160x5) SPUs as well as 40 TAUs and 16 ROPs.
Compare all of that to the Radeon HD 6670 (OEM), which has a clock speed of 800 MHz and a GDDR5 memory speed of 1000 MHz. It also uses a 128-bit memory bus, and makes use of a 40 nm design. It is comprised of 480 SPUs, 24 Texture Address Units, and 8 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the Radeon HD 4870 1GB should perform much faster than the Radeon HD 6670 (OEM) in general. (explain)
Texel RateThe Radeon HD 4870 1GB will be much (more or less 56%) better at AF than the Radeon HD 6670 (OEM). (explain)
Pixel RateIf using high levels of AA is important to you, then the Radeon HD 4870 1GB is superior to the Radeon HD 6670 (OEM), 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 largest amount of data (counted in megabytes per second) that can be moved across the external memory interface in one second. The number is calculated by multiplying the interface width by the speed of its memory. If it uses DDR memory, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied in one second. This is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly write to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.