Compare any two graphics cards:
GeForce GTS 450 vs Radeon HD 7770
IntroThe GeForce GTS 450 comes with a GPU core clock speed of 783 MHz, and the 512 MB of GDDR5 memory is set to run at 902 MHz through a 128-bit bus. It also is made up of 192 SPUs, 32 TAUs, and 16 ROPs.
Compare that to the Radeon HD 7770, which features GPU clock speed of 1000 MHz, and 1024 MB of GDDR5 memory running at 1125 MHz through a 128-bit bus. It also is comprised of 640 Stream Processors, 40 TAUs, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 7770 should in theory be quite a bit superior to the GeForce GTS 450 overall. (explain)
Texel RateThe Radeon HD 7770 will be quite a bit (more or less 60%) faster with regards to anisotropic filtering than the GeForce GTS 450. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon HD 7770 is superior to the GeForce GTS 450, by a large margin. (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 maximum amount of information (measured in megabytes per second) that can be transported over the external memory interface in one second. It's worked out by multiplying the bus width by the speed of its memory. If it uses DDR type memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This number is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly write to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.