Compare any two graphics cards:
Radeon HD 4850 1GB vs Radeon HD 5870
IntroThe Radeon HD 4850 1GB uses a 55 nm design. AMD has set the core frequency at 625 MHz. The GDDR4 memory works at a speed of 993 MHz on this model. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.
Compare that to the Radeon HD 5870, which has a GPU core clock speed of 850 MHz, and 1024 MB of GDDR5 memory running at 1200 MHz through a 256-bit bus. It also is comprised of 1600(320x5) SPUs, 80 TAUs, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 5870 is 142% faster than the Radeon HD 4850 1GB overall, due to its higher data rate. (explain)
Texel RateThe Radeon HD 5870 is a lot (approximately 172%) faster with regards to AF than the Radeon HD 4850 1GB. (explain)
Pixel RateThe Radeon HD 5870 should be a lot (more or less 172%) more effective at full screen anti-aliasing than the Radeon HD 4850 1GB, and also capable of handling higher 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: Bandwidth is the largest amount of data (in units of megabytes per second) that can be moved over the external memory interface in a second. It's worked out by multiplying the bus width by the speed of its memory. If it uses DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better 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 number of texture map elements (texels) that are applied in one second. This figure is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to its local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.