Compare any two graphics cards:
GeForce GT 420 vs Radeon HD 5450
IntroThe GeForce GT 420 features a GPU clock speed of 700 MHz, and the 2048 MB of GDDR3 memory is set to run at 900 MHz through a 128-bit bus. It also features 48 SPUs, 8 TAUs, and 4 Raster Operation Units.
Compare all that to the Radeon HD 5450, which has GPU clock speed of 650 MHz, and 512 MB of DDR3 memory set to run at 800 MHz through a 64-bit bus. It also is made up of 80(16x5) SPUs, 8 Texture Address Units, and 4 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the GeForce GT 420 should theoretically be much better than the Radeon HD 5450 in general. (explain)
Texel RateThe GeForce GT 420 will be a bit (about 8%) more effective at AF than the Radeon HD 5450. (explain)
Pixel RateIf using a high resolution is important to you, then the GeForce GT 420 is the winner, though not by far. (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 data (in units of MB per second) that can be transferred past the external memory interface in a second. It is calculated by multiplying the interface width by the speed of its memory. If it uses DDR RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the better 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 applied in one second. This figure is calculated by multiplying the total texture units by the core speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly record to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.