Compare any two graphics cards:
Radeon HD 4650 512MB vs Radeon HD 6450 (OEM) 1GB
IntroThe Radeon HD 4650 512MB has a clock speed of 600 MHz and a DDR2 memory speed of 500 MHz. It also features a 128-bit bus, and makes use of a 55 nm design. It is made up of 320(64x5) SPUs, 32 Texture Address Units, and 8 ROPs.
Compare that to the Radeon HD 6450 (OEM) 1GB, which features GPU clock speed of 750 MHz, and 1024 MB of GDDR5 RAM running at 900 MHz through a 64-bit bus. It also is made up of 160 SPUs, 8 TAUs, and 4 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 6450 (OEM) 1GB should in theory be quite a bit faster than the Radeon HD 4650 512MB in general. (explain)
Texel RateThe Radeon HD 4650 512MB is much (about 220%) more effective at AF than the Radeon HD 6450 (OEM) 1GB. (explain)
Pixel RateIf running with high levels of AA is important to you, then the Radeon HD 4650 512MB 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: Bandwidth is the max amount of data (measured in MB per second) that can be moved across the external memory interface in one second. The number is worked out by multiplying the bus width by its memory speed. If it uses DDR type memory, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better 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 can be processed in one second. This is calculated by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly record to the local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.