Compare any two graphics cards:
Radeon HD 5670 vs Radeon HD 5770
IntroThe Radeon HD 5670 has a GPU core clock speed of 775 MHz, and the 1024 MB of GDDR5 memory runs at 1000 MHz through a 128-bit bus. It also is comprised of 400(80x5) Stream Processors, 20 Texture Address Units, and 8 ROPs.
Compare all of that to the Radeon HD 5770, which features a core clock frequency of 850 MHz and a GDDR5 memory speed of 1200 MHz. It also features a 128-bit memory bus, and makes use of a 40 nm design. It is comprised of 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 5770 should be 20% quicker than the Radeon HD 5670 in general, due to its greater data rate. (explain)
Texel RateThe Radeon HD 5770 is quite a bit (approximately 119%) faster with regards to texture filtering than the Radeon HD 5670. (explain)
Pixel RateIf running with a high resolution is important to you, then the Radeon HD 5770 is a better choice, by a large margin. (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 (counted in megabytes per second) that can be transferred past the external memory interface within a second. It's calculated by multiplying the interface width by the speed of its memory. If the card has DDR type memory, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed in one second. This is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The better 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 the graphics card could possibly record to its local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - aka 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, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.