Compare any two graphics cards:
GeForce GTX 260 vs Radeon HD 4890 1GB
IntroThe GeForce GTX 260 has a GPU core speed of 576 MHz, and the 896 MB of GDDR3 memory is set to run at 999 MHz through a 448-bit bus. It also is comprised of 192 Stream Processors, 64 TAUs, and 28 Raster Operation Units.
Compare all of that to the Radeon HD 4890 1GB, which uses a 55 nm design. AMD has clocked the core speed at 1000 MHz. The GDDR5 RAM is set to run at a speed of 975 MHz on this card. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Radeon HD 4890 1GB should theoretically be a bit superior to the GeForce GTX 260 overall. (explain)
Texel RateThe Radeon HD 4890 1GB should be a bit (about 9%) faster with regards to texture filtering than the GeForce GTX 260. (explain)
Pixel RateIf using a high resolution is important to you, then the GeForce GTX 260 is a better choice, but only just. (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 (in units of MB per second) that can be moved over the external memory interface within a second. The number is calculated by multiplying the interface width by its memory clock speed. In the case of DDR type RAM, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, 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 figure is worked out by multiplying the total amount of texture units by the core clock 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 applied in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly record to its local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of ROPs by the clock 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 memory bandwidth is, the lower the ability to reach the max fill rate.