Compare any two graphics cards:
GeForce 9800 GTX vs GeForce GTS 250 1GB
IntroThe GeForce 9800 GTX comes with clock speeds of 675 MHz on the GPU, and 1100 MHz on the 512 MB of GDDR3 RAM. It features 128 SPUs along with 64 Texture Address Units and 16 Rasterization Operator Units.
Compare all of that to the GeForce GTS 250 1GB, which features a clock frequency of 738 MHz and a GDDR3 memory frequency of 1100 MHz. It also uses a 256-bit bus, and uses a 65/55 nm design. It is comprised of 128 SPUs, 64 TAUs, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same memory bandwidth, so theoretically they should perform exactly the same. (explain)
Texel RateThe GeForce GTS 250 1GB should be a bit (approximately 9%) faster with regards to AF than the GeForce 9800 GTX. (explain)
Pixel RateThe GeForce GTS 250 1GB will be just a bit (approximately 9%) more effective at AA than the GeForce 9800 GTX, and also will be capable of handling higher screen resolutions better. (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 information (in units of megabytes per second) that can be transferred across the external memory interface within a second. It's calculated by multiplying the card's interface width by its memory speed. In the case of DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied in one second. This figure is worked out by multiplying the total texture units of the card by the core speed of the chip. The higher the texel rate, the better the 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 maximum number of pixels that the graphics chip could possibly record to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.