Compare any two graphics cards:
Radeon HD 3870 1GB vs Radeon HD 4350
IntroThe Radeon HD 3870 1GB comes with a GPU core clock speed of 775 MHz, and the 1024 MB of GDDR4 RAM runs at 1125 MHz through a 256-bit bus. It also is made up of 320(64x5) Stream Processors, 16 Texture Address Units, and 16 Raster Operation Units.
Compare those specs to the Radeon HD 4350, which uses a 55 nm design. AMD has set the core speed at 575 MHz. The DDR2 RAM is set to run at a frequency of 500 MHz on this specific model. It features 80(16x5) SPUs along with 8 TAUs and 4 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 3870 1GB should in theory be much faster than the Radeon HD 4350 in general. (explain)
Texel RateThe Radeon HD 3870 1GB should be much (approximately 170%) faster with regards to AF than the Radeon HD 4350. (explain)
Pixel RateIf using a high resolution is important to you, then the Radeon HD 3870 1GB is the winner, by far. (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.
Memory Bandwidth: Bandwidth is the maximum amount of information (counted in MB per second) that can be transferred over the external memory interface in one second. The number is worked out by multiplying the bus width by its memory speed. If the card has DDR RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied per second. This number is worked out by multiplying the total number of texture units by the core clock speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly write to the local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the amount 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 fill rate also depends on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.