Compare any two graphics cards:
Radeon HD 4850 1GB vs Radeon HD 5870
IntroThe Radeon HD 4850 1GB comes with core clock speeds of 625 MHz on the GPU, and 993 MHz on the 1024 MB of GDDR4 RAM. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.
Compare all that to the Radeon HD 5870, which has core clock speeds of 850 MHz on the GPU, and 1200 MHz on the 1024 MB of GDDR5 RAM. It features 1600(320x5) SPUs as well as 80 Texture Address Units and 32 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Radeon HD 5870 should theoretically be a lot better than the Radeon HD 4850 1GB overall. (explain)
Texel RateThe Radeon HD 5870 should be quite a bit (approximately 172%) faster with regards to texture filtering than the Radeon HD 4850 1GB. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the Radeon HD 5870 is superior to the Radeon HD 4850 1GB, 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 MB per second) that can be moved past the external memory interface in one second. It's worked out by multiplying the interface width by its memory clock speed. If it uses DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied per second. This is calculated by multiplying the total texture units by the core speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly write to its local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the the core clock speed. 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 fill rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.