Compare any two graphics cards:
Radeon HD 4870 512MB vs Radeon HD 7850
IntroThe Radeon HD 4870 512MB features a core clock speed of 750 MHz and a GDDR5 memory frequency of 900 MHz. It also features a 256-bit memory bus, and uses a 55 nm design. It is comprised of 800(160x5) SPUs, 40 TAUs, and 16 ROPs.
Compare that to the Radeon HD 7850, which has GPU core speed of 860 MHz, and 2048 MB of GDDR5 RAM set to run at 1200 MHz through a 256-bit bus. It also features 1024 Stream Processors, 64 TAUs, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7850 will be 33% faster than the Radeon HD 4870 512MB overall, due to its higher bandwidth. (explain)
Texel RateThe Radeon HD 7850 should be quite a bit (about 83%) better at anisotropic filtering than the Radeon HD 4870 512MB. (explain)
Pixel RateThe Radeon HD 7850 should be much (more or less 129%) faster with regards to AA than the Radeon HD 4870 512MB, and also will be capable of handling higher resolutions without slowing down too much. (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.
Price ComparisonPlease note that the price comparisons are based on search keywords, and might not be the exact same card listed on this page. We have no control over the accuracy of their search results.
Memory Bandwidth: Bandwidth is the max amount of data (measured in megabytes per second) that can be moved over the external memory interface in a second. It is calculated by multiplying the bus width by the speed of its memory. If it uses DDR type RAM, it must 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 anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied in one second. This figure is calculated by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Render Output Units 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 output rate is also dependant on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.