Compare any two graphics cards:
GeForce GT 420 vs Radeon HD 5450
IntroThe GeForce GT 420 uses a 40 nm design. nVidia has set the core frequency at 700 MHz. The GDDR3 memory works at a speed of 900 MHz on this particular card. It features 48 SPUs along with 8 Texture Address Units and 4 Rasterization Operator Units.
Compare all that to the Radeon HD 5450, which comes with a clock frequency of 650 MHz and a DDR3 memory frequency of 800 MHz. It also features a 64-bit bus, and uses a 40 nm design. It is made up of 80(16x5) SPUs, 8 TAUs, and 4 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce GT 420 should in theory be quite a bit faster than the Radeon HD 5450 in general. (explain)
Texel RateThe GeForce GT 420 will be just a bit (about 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, though only just barely. (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 maximum amount of information (measured in MB per second) that can be moved past the external memory interface in one second. It is worked out by multiplying the card's interface width by its memory clock speed. If it uses DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This is calculated by multiplying the total number of texture units by the core clock speed of the chip. The higher this number, the better the video card will be at 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 in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.