Compare any two graphics cards:
GeForce GT 420 vs Radeon HD 5450
IntroThe GeForce GT 420 comes with core speeds of 700 MHz on the GPU, and 900 MHz on the 2048 MB of GDDR3 RAM. It features 48 SPUs as well as 8 Texture Address Units and 4 Rasterization Operator Units.
Compare that to the Radeon HD 5450, which uses a 40 nm design. AMD has clocked the core frequency at 650 MHz. The DDR3 memory works at a speed of 800 MHz on this particular card. It features 80(16x5) SPUs as well as 8 TAUs and 4 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the GeForce GT 420 should theoretically be a lot better than the Radeon HD 5450 overall. (explain)
Texel RateThe GeForce GT 420 will be a little bit (about 8%) faster with regards to AF than the Radeon HD 5450. (explain)
Pixel RateThe GeForce GT 420 should be a bit (more or less 8%) faster with regards to full screen anti-aliasing than the Radeon HD 5450, and also should be capable of handling higher resolutions while still performing well. (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 largest amount of data (measured in megabytes per second) that can be transferred across the external memory interface in a second. It is calculated by multiplying the card's interface width by its memory speed. If the card has DDR type RAM, it must 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, HDR and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed 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 higher the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip can possibly record to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the max fill rate.