Compare any two graphics cards:
GeForce GT 440 1.5GB vs Radeon HD 4890 2GB
IntroThe GeForce GT 440 1.5GB features a GPU clock speed of 594 MHz, and the 1536 MB of GDDR3 RAM runs at 900 MHz through a 192-bit bus. It also features 144 Stream Processors, 24 Texture Address Units, and 24 ROPs.
Compare those specs to the Radeon HD 4890 2GB, which comes with core clock speeds of 1000 MHz on the GPU, and 975 MHz on the 2048 MB of GDDR5 RAM. It features 800(160x5) SPUs along with 40 TAUs and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 4890 2GB should theoretically perform much faster than the GeForce GT 440 1.5GB in general. (explain)
Texel RateThe Radeon HD 4890 2GB is much (more or less 181%) faster with regards to AF than the GeForce GT 440 1.5GB. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon HD 4890 2GB is the winner, 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 maximum amount of data (counted in MB per second) that can be transported across the external memory interface within a second. It is worked out by multiplying the card's bus width by the speed of its memory. If it uses DDR memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the better 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 processed per second. This is calculated by multiplying the total number of texture units by the core speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the most pixels the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.