Compare any two graphics cards:
GeForce 8600 GT 256MB DDR2 vs Radeon HD 5450
IntroThe GeForce 8600 GT 256MB DDR2 comes with clock speeds of 540 MHz on the GPU, and 400 MHz on the 256 MB of DDR2 memory. It features 32 SPUs as well as 16 TAUs and 8 Rasterization Operator Units.
Compare all that to the Radeon HD 5450, which comes with clock speeds of 650 MHz on the GPU, and 800 MHz on the 512 MB of DDR3 memory. It features 80(16x5) SPUs along with 8 Texture Address Units and 4 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same memory bandwidth, so theoretically they should have the same performance. (explain)
Texel RateThe GeForce 8600 GT 256MB DDR2 will be a lot (approximately 66%) better at texture filtering than the Radeon HD 5450. (explain)
Pixel RateThe GeForce 8600 GT 256MB DDR2 will be much (about 66%) more effective at full screen anti-aliasing than the Radeon HD 5450, and capable of handling 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: Bandwidth is the largest amount of data (counted in megabytes per second) that can be transported past the external memory interface in a second. The number is calculated by multiplying the card's interface width by the speed of its memory. If the card has DDR type RAM, it must 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 AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total amount of texture units by the core speed of the chip. The better this number, 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 maximum number of pixels the graphics card could possibly write to its local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the max fill rate.