Compare any two graphics cards:
GeForce GTX 650 vs Radeon HD 7770
IntroThe GeForce GTX 650 uses a 28 nm design. nVidia has clocked the core speed at 1058 MHz. The GDDR5 memory works at a speed of 1250 MHz on this particular model. It features 384 SPUs as well as 32 TAUs and 16 Rasterization Operator Units.
Compare all that to the Radeon HD 7770, which has a core clock speed of 1000 MHz and a GDDR5 memory frequency of 1125 MHz. It also makes use of a 128-bit bus, and makes use of a 28 nm design. It is made up of 640 SPUs, 40 Texture Address Units, and 16 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the GeForce GTX 650 will be 11% faster than the Radeon HD 7770 in general, because of its higher data rate. (explain)
Texel RateThe Radeon HD 7770 is just a bit (approximately 18%) more effective at AF than the GeForce GTX 650. (explain)
Pixel RateThe GeForce GTX 650 will be a bit (about 6%) better at AA than the Radeon HD 7770, and will be capable of handling higher screen 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 maximum amount of data (in units of MB per second) that can be transported past the external memory interface in a second. It's worked out by multiplying the card's bus width by the speed of its memory. In the case of DDR RAM, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher 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 number of texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total texture units by the core speed of the chip. The better this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to its local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the number of colour ROPs 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 also depends 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.