Compare any two graphics cards:
GeForce GTX 650 vs Radeon HD 4890 2GB
IntroThe GeForce GTX 650 features a core clock speed of 1058 MHz and a GDDR5 memory speed of 1250 MHz. It also features a 128-bit bus, and uses a 28 nm design. It is made up of 384 SPUs, 32 Texture Address Units, and 16 Raster Operation Units.
Compare those specifications to the Radeon HD 4890 2GB, which uses a 55 nm design. AMD has clocked the core frequency at 1000 MHz. The GDDR5 memory works at a frequency of 975 MHz on this particular card. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 4890 2GB should be quite a bit faster than the GeForce GTX 650 in general. (explain)
Texel RateThe Radeon HD 4890 2GB should be just a bit (more or less 18%) faster with regards to anisotropic filtering than the GeForce GTX 650. (explain)
Pixel RateThe GeForce GTX 650 will be a bit (more or less 6%) more effective at anti-aliasing than the Radeon HD 4890 2GB, and also should be capable of handling higher resolutions without losing too much performance. (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 (measured in MB per second) that can be transported past the external memory interface in one second. The number is worked out by multiplying the card's bus width by its memory clock speed. If it uses DDR type RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This is calculated by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher this number, the better the graphics 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 maximum number of pixels the video card can possibly record to its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.