Compare any two graphics cards:
GeForce 9800 GT 1GB vs Radeon HD 7850
IntroThe GeForce 9800 GT 1GB has core clock speeds of 600 MHz on the GPU, and 900 MHz on the 1024 MB of GDDR3 RAM. It features 112 SPUs along with 56 Texture Address Units and 16 ROPs.
Compare those specifications to the Radeon HD 7850, which features GPU clock speed of 860 MHz, and 2048 MB of GDDR5 RAM running at 1200 MHz through a 256-bit bus. It also is made up of 1024 Stream Processors, 64 Texture Address Units, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 7850 should be 167% quicker than the GeForce 9800 GT 1GB overall, due to its higher data rate. (explain)
Texel RateThe Radeon HD 7850 will be quite a bit (about 64%) faster with regards to texture filtering than the GeForce 9800 GT 1GB. (explain)
Pixel RateThe Radeon HD 7850 should be much (more or less 187%) better at full screen anti-aliasing than the GeForce 9800 GT 1GB, and also should be capable of handling higher 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: Memory bandwidth is the maximum amount of information (in units of megabytes per second) that can be moved over the external memory interface in one second. It is calculated by multiplying the interface width by its memory speed. In the case of DDR type memory, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster 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 texture map elements (texels) that can be processed per second. This is worked out by multiplying the total number of texture units by the core clock speed of the chip. The higher this number, the better the graphics card will be at 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 chip can possibly record to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka 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 of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.