Compare any two graphics cards:
GeForce 9800 GTX vs GeForce GTS 250 1GB
IntroThe GeForce 9800 GTX comes with a clock frequency of 675 MHz and a GDDR3 memory frequency of 1100 MHz. It also makes use of a 256-bit memory bus, and makes use of a 65 nm design. It features 128 SPUs, 64 Texture Address Units, and 16 ROPs.
Compare those specifications to the GeForce GTS 250 1GB, which makes use of a 65/55 nm design. nVidia has set the core speed at 738 MHz. The GDDR3 RAM is set to run at a speed of 1100 MHz on this card. It features 128 SPUs along with 64 TAUs and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have exactly the same bandwidth, so in theory they should have identical performance. (explain)
Texel RateThe GeForce GTS 250 1GB will be a small bit (more or less 9%) faster with regards to anisotropic filtering than the GeForce 9800 GTX. (explain)
Pixel RateThe GeForce GTS 250 1GB should be a little bit (approximately 9%) better at AA than the GeForce 9800 GTX, and should be capable of handling higher screen resolutions more effectively. (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 (counted in MB per second) that can be moved across the external memory interface in one second. It is calculated by multiplying the card's interface width by its memory clock speed. In the case of DDR memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This figure is worked out by multiplying the total texture units of the card by the core clock speed of the chip. The higher this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly write to its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant 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 max fill rate.