Compare any two graphics cards:
GeForce GT 420 vs Radeon HD 6670 (OEM) 1GB
IntroThe GeForce GT 420 features a GPU core speed of 700 MHz, and the 2048 MB of GDDR3 memory runs at 900 MHz through a 128-bit bus. It also is made up of 48 SPUs, 8 Texture Address Units, and 4 Raster Operation Units.
Compare those specifications to the Radeon HD 6670 (OEM) 1GB, which comes with a clock speed of 800 MHz and a GDDR5 memory frequency of 1000 MHz. It also uses a 128-bit memory bus, and makes use of a 40 nm design. It is made up of 480 SPUs, 24 TAUs, and 8 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 6670 (OEM) 1GB should theoretically be much faster than the GeForce GT 420 in general. (explain)
Texel RateThe Radeon HD 6670 (OEM) 1GB is much (about 243%) better at AF than the GeForce GT 420. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the Radeon HD 6670 (OEM) 1GB is the winner, by far. (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 largest amount of data (in units of megabytes per second) that can be moved past the external memory interface in one second. It is worked out by multiplying the bus width by its memory clock speed. In the case of DDR RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the better 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 number of texture map elements (texels) that can be applied per second. This is worked out by multiplying the total texture units of the card by the core speed of the chip. The better this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.