Compare any two graphics cards:
Radeon HD 4670 1GB vs Radeon HD 5450
IntroThe Radeon HD 4670 1GB has a GPU clock speed of 750 MHz, and the 1024 MB of GDDR4/GDDR3/DDR3/DDR2 RAM runs at 1100 MHz through a 128-bit bus. It also is made up of 320(64x5) SPUs, 32 TAUs, and 8 ROPs.
Compare 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 makes use of a 64-bit memory bus, and uses a 40 nm design. It is made up of 80(16x5) SPUs, 8 Texture Address Units, and 4 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the Radeon HD 4670 1GB should perform a lot faster than the Radeon HD 5450 overall. (explain)
Texel RateThe Radeon HD 4670 1GB will be quite a bit (approximately 362%) faster with regards to anisotropic filtering than the Radeon HD 5450. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the Radeon HD 4670 1GB is the winner, and very much so. (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 (counted in megabytes per second) that can be moved past the external memory interface within a second. The number is calculated by multiplying the card's bus width by the speed of its memory. If it uses DDR type memory, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied in one second. This is worked out by multiplying the total amount of texture units 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 in one second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.