Compare any two graphics cards:
Radeon HD 5770 vs Radeon HD 7770
IntroThe Radeon HD 5770 features core speeds of 850 MHz on the GPU, and 1200 MHz on the 1024 MB of GDDR5 RAM. It features 800(160x5) SPUs as well as 40 Texture Address Units and 16 ROPs.
Compare those specifications to the Radeon HD 7770, which has a clock speed of 1000 MHz and a GDDR5 memory frequency of 1125 MHz. It also makes use of a 128-bit bus, and uses a 28 nm design. It is comprised of 640 SPUs, 40 Texture Address Units, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 5770 should theoretically be just a bit faster than the Radeon HD 7770 in general. (explain)
Texel RateThe Radeon HD 7770 should be a bit (about 18%) more effective at texture filtering than the Radeon HD 5770. (explain)
Pixel RateThe Radeon HD 7770 is a small bit (about 18%) better at AA than the Radeon HD 5770, and also able to handle higher resolutions without slowing down too much. (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 max amount of information (measured in megabytes per second) that can be transported past the external memory interface in one second. It's worked out by multiplying the bus width by its memory speed. In the case of DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly write 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 clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.