Compare any two graphics cards:
GeForce 8400 GS 512MB vs GeForce 9500 GT DDR2
IntroThe GeForce 8400 GS 512MB features a GPU core speed of 650 MHz, and the 512 MB of DDR2 RAM is set to run at 400 MHz through a 64-bit bus. It also is made up of 16 SPUs, 8 Texture Address Units, and 4 ROPs.
Compare that to the GeForce 9500 GT DDR2, which comes with GPU clock speed of 550 MHz, and 256 MB of DDR2 RAM running at 500 MHz through a 128-bit bus. It also is made up of 32 Stream Processors, 16 Texture Address Units, and 8 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the GeForce 9500 GT DDR2 should be quite a bit faster than the GeForce 8400 GS 512MB overall. (explain)
Texel RateThe GeForce 9500 GT DDR2 should be a lot (more or less 69%) better at AF than the GeForce 8400 GS 512MB. (explain)
Pixel RateIf using a high resolution is important to you, then the GeForce 9500 GT DDR2 is a better choice, 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 max amount of data (counted in megabytes per second) that can be transported past the external memory interface in a second. It is calculated by multiplying the bus width by its memory speed. If the card has DDR memory, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied in one second. This figure is calculated by multiplying the total number 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 handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.