Compare any two graphics cards:
Radeon HD 5850 vs Radeon HD 7850
IntroThe Radeon HD 5850 has a core clock speed of 725 MHz and a GDDR5 memory frequency of 1000 MHz. It also makes use of a 256-bit memory bus, and uses a 40 nm design. It is made up of 1440(288x5) SPUs, 72 Texture Address Units, and 32 Raster Operation Units.
Compare that to the Radeon HD 7850, which has GPU core speed of 860 MHz, and 2048 MB of GDDR5 memory running at 1200 MHz through a 256-bit bus. It also features 1024 SPUs, 64 Texture Address Units, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 7850 will be 20% faster than the Radeon HD 5850 overall, due to its higher bandwidth. (explain)
Texel RateThe Radeon HD 7850 should be a little bit (more or less 5%) more effective at anisotropic filtering than the Radeon HD 5850. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the Radeon HD 7850 is a better choice, but only just. (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 max amount of data (measured in MB per second) that can be transferred across the external memory interface in a second. It's calculated by multiplying the card's bus width by its memory clock speed. If it uses DDR memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied in one second. This is calculated by multiplying the total texture units by the core speed of the chip. The better the texel rate, the better the graphics 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 most pixels the video card can possibly write to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.