Compare any two graphics cards:
GeForce GTX 550 Ti vs Radeon HD 4850 512MB
IntroThe GeForce GTX 550 Ti has a clock frequency of 900 MHz and a GDDR5 memory frequency of 1026 MHz. It also makes use of a 192-bit memory bus, and makes use of a 40 nm design. It is comprised of 192 SPUs, 32 Texture Address Units, and 24 ROPs.
Compare those specifications to the Radeon HD 4850 512MB, which uses a 55 nm design. AMD has clocked the core speed at 625 MHz. The GDDR3 RAM works at a speed of 993 MHz on this particular model. It features 800(160x5) SPUs as well as 40 Texture Address Units and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the GeForce GTX 550 Ti should theoretically be quite a bit superior to the Radeon HD 4850 512MB in general. (explain)
Texel RateThe GeForce GTX 550 Ti should be a little bit (about 15%) more effective at texture filtering than the Radeon HD 4850 512MB. (explain)
Pixel RateThe GeForce GTX 550 Ti will be quite a bit (about 116%) more effective at anti-aliasing than the Radeon HD 4850 512MB, and also 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.
Memory Bandwidth: Memory bandwidth is the maximum amount of data (in units of megabytes per second) that can be transported over the external memory interface in one second. The number is calculated by multiplying the bus width by its memory clock speed. If the card has DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied 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 better this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics 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 colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.