Compare any two graphics cards:
Radeon HD 4850 1GB vs Radeon HD 5870
IntroThe Radeon HD 4850 1GB features a GPU core speed of 625 MHz, and the 1024 MB of GDDR4 memory runs at 993 MHz through a 256-bit bus. It also is comprised of 800(160x5) Stream Processors, 40 TAUs, and 16 Raster Operation Units.
Compare that to the Radeon HD 5870, which comes with a clock speed of 850 MHz and a GDDR5 memory frequency of 1200 MHz. It also uses a 256-bit memory bus, and uses a 40 nm design. It features 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)
The Radeon HD 5870 should theoretically be much faster than the Radeon HD 4850 1GB overall. (explain)
Texel RateThe Radeon HD 5870 will be quite a bit (about 172%) more effective at texture filtering than the Radeon HD 4850 1GB. (explain)
Pixel RateThe Radeon HD 5870 is a lot (approximately 172%) more effective at full screen anti-aliasing than the Radeon HD 4850 1GB, and should be capable of handling higher resolutions while still performing well. (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 maximum amount of data (measured in MB per second) that can be transported across the external memory interface in a second. The number is worked out by multiplying the interface width by its memory speed. If the card has DDR memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the faster 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 texture map elements (texels) that are applied per second. This number 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 graphics 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 most pixels the video card could possibly write to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the amount of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.