Compare any two graphics cards:
GeForce GT 420 vs Radeon HD 6670 (OEM) 1GB
IntroThe GeForce GT 420 makes use of a 40 nm design. nVidia has set the core speed at 700 MHz. The GDDR3 RAM is set to run at a speed of 900 MHz on this model. It features 48 SPUs as well as 8 TAUs and 4 ROPs.
Compare those specifications to the Radeon HD 6670 (OEM) 1GB, which makes use of a 40 nm design. AMD has clocked the core speed at 800 MHz. The GDDR5 memory is set to run at a frequency of 1000 MHz on this particular model. It features 480 SPUs along with 24 Texture Address Units and 8 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the Radeon HD 6670 (OEM) 1GB should perform much faster than the GeForce GT 420 overall. (explain)
Texel RateThe Radeon HD 6670 (OEM) 1GB will be much (more or less 243%) better at anisotropic filtering than the GeForce GT 420. (explain)
Pixel RateThe Radeon HD 6670 (OEM) 1GB will be much (approximately 129%) better at FSAA than the GeForce GT 420, and able to handle higher screen resolutions while still performing well. (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 MB per second) that can be transferred over the external memory interface in a second. It's worked out by multiplying the card's bus width by the speed of its memory. In the case of DDR type RAM, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the bandwidth is, 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 amount of texture map elements (texels) that are processed per second. This figure is worked out by multiplying the total number of texture units by the core speed of the chip. The higher the texel rate, 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 amount of pixels that the graphics card can possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel 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 potential to reach the max fill rate.