Compare any two graphics cards:
GeForce 9800 GT 1GB vs GeForce 9800 GT 512MB
IntroThe GeForce 9800 GT 1GB comes with a GPU core clock speed of 600 MHz, and the 1024 MB of GDDR3 RAM is set to run at 900 MHz through a 256-bit bus. It also features 112 Stream Processors, 56 Texture Address Units, and 16 Raster Operation Units.
Compare those specifications to the GeForce 9800 GT 512MB, which comes with a clock speed of 600 MHz and a GDDR3 memory frequency of 900 MHz. It also features a 256-bit memory bus, and makes use of a 65/55 nm design. It is made up of 112 SPUs, 56 Texture Address Units, and 16 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
Both cards have exactly the same bandwidth, so theoretically they should perform exactly the same. (explain)
Texel RateBoth cards have the exact same texel rate, so in theory they should perform equally good at at AF. (explain)
Pixel RateBoth cards have the exact same pixel rate, so theoretically they should perform equally good at at FSAA, and be able to handle the same screen resolutions. (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.
Price ComparisonPlease note that the price comparisons are based on search keywords, and might not be the exact same card listed on this page. We have no control over the accuracy of their search results.
Memory Bandwidth: Bandwidth is the maximum amount of data (measured in megabytes per second) that can be transferred across 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 type RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's 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 amount of 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 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 maximum amount of pixels that the graphics chip could possibly write to its local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.