Compare any two graphics cards:
GeForce 940M vs GeForce 9800 GT 1GB
IntroThe GeForce 940M comes with a GPU clock speed of 1072 MHz, and the 2048 MB of DDR3 memory is set to run at 1000 MHz through a 64-bit bus. It also is made up of 384 SPUs, 24 Texture Address Units, and 8 Raster Operation Units.
Compare that to the GeForce 9800 GT 1GB, which features a clock speed of 600 MHz and a GDDR3 memory speed of 900 MHz. It also features a 256-bit bus, and makes use of a 65/55 nm design. It features 112 SPUs, 56 TAUs, and 16 ROPs.
Power Usage and Theoretical Benchmarks
In theory, the GeForce 9800 GT 1GB will be 260% quicker than the GeForce 940M overall, because of its higher bandwidth. (explain)
Texel RateThe GeForce 9800 GT 1GB should be a lot (more or less 31%) better at AF than the GeForce 940M. (explain)
Pixel RateIf using a high resolution is important to you, then the GeForce 9800 GT 1GB is a better choice, but it probably won't make a huge difference. (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 information (counted in MB per second) that can be transferred across the external memory interface in one second. The number is worked out by multiplying the bus width by the speed of its memory. In the case of DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one second. This is calculated by multiplying the total amount of texture units by the core speed of the chip. The better the texel rate, the better the graphics 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 most pixels that the graphics card can possibly write to its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.