Compare any two graphics cards:
GeForce 8400 GS 512MB vs GeForce GTS 450 1GB
IntroThe GeForce 8400 GS 512MB comes with a GPU core clock speed of 650 MHz, and the 512 MB of DDR2 RAM runs at 400 MHz through a 64-bit bus. It also is made up of 16 SPUs, 8 TAUs, and 4 Raster Operation Units.
Compare that to the GeForce GTS 450 1GB, which uses a 40 nm design. nVidia has set the core speed at 783 MHz. The GDDR5 RAM is set to run at a speed of 902 MHz on this specific model. It features 192 SPUs along with 32 TAUs and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the GeForce GTS 450 1GB should in theory be quite a bit better than the GeForce 8400 GS 512MB overall. (explain)
Texel RateThe GeForce GTS 450 1GB will be quite a bit (approximately 382%) faster with regards to texture filtering than the GeForce 8400 GS 512MB. (explain)
Pixel RateIf using high levels of AA is important to you, then the GeForce GTS 450 1GB is superior to the GeForce 8400 GS 512MB, 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 largest amount of data (measured in MB per second) that can be moved past the external memory interface within a second. The number is worked out by multiplying the bus width by its memory clock speed. If it uses DDR type RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better 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 number of texture map elements (texels) that can be applied in one second. This figure is calculated by multiplying the total texture units by the core speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.