Compare any two graphics cards:
Radeon HD 4650 512MB vs Radeon HD 6450 (OEM) 1GB
IntroThe Radeon HD 4650 512MB comes with clock speeds of 600 MHz on the GPU, and 500 MHz on the 512 MB of DDR2 RAM. It features 320(64x5) SPUs as well as 32 Texture Address Units and 8 Rasterization Operator Units.
Compare those specs to the Radeon HD 6450 (OEM) 1GB, which uses a 40 nm design. AMD has set the core speed at 750 MHz. The GDDR5 memory works at a frequency of 900 MHz on this particular model. It features 160 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 Radeon HD 6450 (OEM) 1GB should theoretically be quite a bit superior to the Radeon HD 4650 512MB in general. (explain)
Texel RateThe Radeon HD 4650 512MB will be quite a bit (more or less 220%) better at texture filtering than the Radeon HD 6450 (OEM) 1GB. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the Radeon HD 4650 512MB is the winner, by a large margin. (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 information (counted in MB per second) that can be transported over the external memory interface in a second. The number is worked out by multiplying the bus width by its memory clock speed. If it uses DDR type memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the card's 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 number of texture map elements (texels) that can be processed per second. This figure is calculated by multiplying the total amount 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 processed per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly record to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.