Compare any two graphics cards:
GeForce 9800 GTX vs GeForce GTS 250 1GB
IntroThe GeForce 9800 GTX features a clock frequency of 675 MHz and a GDDR3 memory speed of 1100 MHz. It also makes use of a 256-bit bus, and makes use of a 65 nm design. It is comprised of 128 SPUs, 64 Texture Address Units, and 16 Raster Operation Units.
Compare all of that to the GeForce GTS 250 1GB, which has a clock frequency of 738 MHz and a GDDR3 memory frequency of 1100 MHz. It also makes use of a 256-bit memory bus, and uses a 65/55 nm design. It features 128 SPUs, 64 Texture Address Units, and 16 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same memory bandwidth, so theoretically they should have identical performance. (explain)
Texel RateThe GeForce GTS 250 1GB should be a small bit (approximately 9%) more effective at anisotropic filtering than the GeForce 9800 GTX. (explain)
Pixel RateThe GeForce GTS 250 1GB is a small bit (more or less 9%) faster with regards to AA than the GeForce 9800 GTX, and should be capable of handling higher resolutions without slowing down too much. (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 largest amount of information (measured in MB per second) that can be transported past the external memory interface within a second. It is worked out by multiplying the card's interface width by the speed of its memory. In the case of DDR memory, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied in one second. This figure is calculated by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip 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 ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.