Compare any two graphics cards:
GeForce 8500 GT vs Radeon HD 5450
IntroThe GeForce 8500 GT makes use of a 80 nm design. nVidia has clocked the core speed at 450 MHz. The DDR2 RAM works at a frequency of 400 MHz on this particular card. It features 16 SPUs along with 8 Texture Address Units and 4 Rasterization Operator Units.
Compare those specifications to the Radeon HD 5450, which uses a 40 nm design. AMD has set the core frequency at 650 MHz. The DDR3 memory works at a frequency of 800 MHz on this particular model. It features 80(16x5) SPUs as well as 8 TAUs and 4 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have exactly the same memory bandwidth, so theoretically they should have the same performance. (explain)
Texel RateThe Radeon HD 5450 will be quite a bit (approximately 44%) more effective at anisotropic filtering than the GeForce 8500 GT. (explain)
Pixel RateThe Radeon HD 5450 is quite a bit (about 44%) more effective at anti-aliasing than the GeForce 8500 GT, and also able to handle higher screen 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: Memory bandwidth is the maximum amount of information (in units of megabytes per second) that can be transferred over the external memory interface within a second. It's calculated by multiplying the bus width by its memory speed. In the case of DDR RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This number is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly record to its 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 core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.