Compare any two graphics cards:
Radeon HD 4870 1GB vs Radeon HD 6670 (OEM)
IntroThe Radeon HD 4870 1GB has a GPU core clock speed of 750 MHz, and the 1024 MB of GDDR5 RAM runs at 900 MHz through a 256-bit bus. It also is made up of 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.
Compare those specs to the Radeon HD 6670 (OEM), which has GPU clock speed of 800 MHz, and 512 MB of GDDR5 RAM set to run at 1000 MHz through a 128-bit bus. It also is made up of 480 SPUs, 24 Texture Address Units, and 8 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 4870 1GB should be much faster than the Radeon HD 6670 (OEM) overall. (explain)
Texel RateThe Radeon HD 4870 1GB is a lot (about 56%) faster with regards to anisotropic filtering than the Radeon HD 6670 (OEM). (explain)
Pixel RateThe Radeon HD 4870 1GB will be quite a bit (more or less 88%) faster with regards to anti-aliasing than the Radeon HD 6670 (OEM), and should be capable of handling higher screen resolutions without losing too much performance. (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 maximum amount of data (in units of MB per second) that can be moved across the external memory interface in one second. The number is calculated by multiplying the card's interface width by its memory clock speed. If it uses DDR memory, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This is calculated by multiplying the total number of texture units of the card by the core speed of the chip. The better the texel rate, the better the card will be at handling 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 can possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.