Compare any two graphics cards:
Radeon HD 4850 1GB vs Radeon HD 7770
IntroThe Radeon HD 4850 1GB uses a 55 nm design. AMD has clocked the core speed at 625 MHz. The GDDR4 RAM works at a speed of 993 MHz on this specific model. It features 800(160x5) SPUs along with 40 Texture Address Units and 16 ROPs.
Compare that to the Radeon HD 7770, which features core clock speeds of 1000 MHz on the GPU, and 1125 MHz on the 1024 MB of GDDR5 memory. It features 640 SPUs along with 40 TAUs and 16 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7770 will be 13% quicker than the Radeon HD 4850 1GB overall, due to its higher data rate. (explain)
Texel RateThe Radeon HD 7770 is quite a bit (more or less 60%) better at AF than the Radeon HD 4850 1GB. (explain)
Pixel RateThe Radeon HD 7770 will be quite a bit (about 60%) faster with regards to AA than the Radeon HD 4850 1GB, and will 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: Memory bandwidth is the largest amount of data (measured in MB per second) that can be moved over the external memory interface within a second. The number is calculated by multiplying the bus width by its memory speed. If the card has DDR type memory, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied per second. This number is calculated by multiplying the total number of texture units by the core speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to its local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. 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 lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.