Compare any two graphics cards:
Radeon HD 4850 512MB vs Radeon R7 250
IntroThe Radeon HD 4850 512MB has a GPU core speed of 625 MHz, and the 512 MB of GDDR3 RAM runs at 993 MHz through a 256-bit bus. It also is made up of 800(160x5) Stream Processors, 40 Texture Address Units, and 16 Raster Operation Units.
Compare those specs to the Radeon R7 250, which comes with a clock frequency of 1000 MHz and a GDDR5 memory frequency of 1150 MHz. It also makes use of a 128-bit memory bus, and uses a 28 nm design. It is made up of 384 SPUs, 24 Texture Address Units, and 8 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon R7 250 will be 16% quicker than the Radeon HD 4850 512MB overall, because of its greater data rate. (explain)
Texel RateThe Radeon HD 4850 512MB is a little bit (about 4%) faster with regards to texture filtering than the Radeon R7 250. (explain)
Pixel RateThe Radeon HD 4850 512MB is much (about 25%) faster with regards to FSAA than the Radeon R7 250, and also should be capable of handling higher screen resolutions more effectively. (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 information (in units of megabytes per second) that can be transported over the external memory interface within a second. It's worked out by multiplying the interface width by its memory speed. In the case of DDR type RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This number is calculated by multiplying the total texture units by the core 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 processed per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly record to the local memory in a second - measured in millions of pixels per second. The number is worked out 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 filling the screen with pixels (the image). The actual pixel rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.