Compare any two graphics cards:
GeForce GTX 285 1GB vs Radeon HD 4890 1GB
IntroThe GeForce GTX 285 1GB features a GPU core speed of 648 MHz, and the 1024 MB of GDDR3 memory is set to run at 1242 MHz through a 512-bit bus. It also features 240 Stream Processors, 80 TAUs, and 32 ROPs.
Compare those specs to the Radeon HD 4890 1GB, which comes with core speeds of 1000 MHz on the GPU, and 975 MHz on the 1024 MB of GDDR5 memory. It features 800(160x5) SPUs as well as 40 Texture Address Units and 16 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the GeForce GTX 285 1GB should theoretically be much superior to the Radeon HD 4890 1GB in general. (explain)
Texel RateThe GeForce GTX 285 1GB is much (more or less 30%) better at anisotropic filtering than the Radeon HD 4890 1GB. (explain)
Pixel RateThe GeForce GTX 285 1GB is a lot (more or less 30%) better at anti-aliasing than the Radeon HD 4890 1GB, and should be able to handle higher screen resolutions without losing too much performance. (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 maximum amount of information (counted in MB per second) that can be transported across the external memory interface within a second. It's worked out by multiplying the card's bus width by its memory speed. If it uses DDR type memory, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied per second. This figure is calculated by multiplying the total amount of texture units by the core speed of the chip. The higher this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly write to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.