Compare any two graphics cards:
Radeon HD 6770 1GB vs Radeon R9 M275X
IntroThe Radeon HD 6770 1GB features a GPU core clock speed of 900 MHz, and the 1024 MB of GDDR5 memory runs at 1050 MHz through a 128-bit bus. It also is comprised of 800 Stream Processors, 40 Texture Address Units, and 16 Raster Operation Units.
Compare those specs to the Radeon R9 M275X, which has GPU clock speed of 900 MHz, and 2048 MB of GDDR5 memory set to run at 1125 MHz through a 128-bit bus. It also features 640 SPUs, 40 Texture Address Units, and 16 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the Radeon R9 M275X should perform a bit faster than the Radeon HD 6770 1GB overall. (explain)
Texel RateBoth cards have exactly the same texel rate, so theoretically they should perform equally good at at anisotropic filtering. (explain)
Pixel RateBoth cards have exactly the same pixel rate, so theoretically they should be equally good at at AA, and be able to handle the same resolutions. (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 largest amount of information (counted in megabytes per second) that can be transferred over the external memory interface in a second. The number is calculated by multiplying the bus width by the speed of its memory. In the case of DDR type memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, 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 amount of texture map elements (texels) that are applied in one second. This number is calculated by multiplying the total texture units by the core clock speed of the chip. The higher the texel rate, the better the 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 that the graphics card can possibly write to the 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 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 rate is also dependant 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.