Compare any two graphics cards:
GeForce GT 420 vs Radeon HD 5450
IntroThe GeForce GT 420 comes with a GPU core 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 Texture Address Units, and 4 ROPs.
Compare those specs to the Radeon HD 5450, which uses a 40 nm design. AMD has clocked the core speed at 650 MHz. The DDR3 RAM runs at a speed of 800 MHz on this card. It features 80(16x5) SPUs as well as 8 TAUs and 4 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce GT 420 should in theory be much faster than the Radeon HD 5450 overall. (explain)
Texel RateThe GeForce GT 420 is a bit (more or less 8%) better at AF than the Radeon HD 5450. (explain)
Pixel RateIf running with a high screen resolution is important to you, then the GeForce GT 420 is superior to the Radeon HD 5450, but it probably won't make a huge difference. (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 max amount of data (measured in megabytes per second) that can be moved over the external memory interface in one second. The number is worked out by multiplying the bus width by the speed of its memory. If it uses DDR RAM, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This is calculated by multiplying the total texture units by the core speed of the chip. The better the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly write to the 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 drawing the pixels (image) on the screen. The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.