Compare any two graphics cards:
GeForce GT 640 DDR3 vs Radeon HD 7750
IntroThe GeForce GT 640 DDR3 uses a 28 nm design. nVidia has set the core speed at 900 MHz. The DDR3 RAM runs at a frequency of 1782 MHz on this particular model. It features 384 SPUs along with 32 Texture Address Units and 16 Rasterization Operator Units.
Compare those specifications to the Radeon HD 7750, which comes with core clock speeds of 800 MHz on the GPU, and 1125 MHz on the 1024 MB of GDDR5 memory. It features 512 SPUs as well as 32 TAUs and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 7750 will be 26% faster than the GeForce GT 640 DDR3 overall, because of its greater bandwidth. (explain)
Texel RateThe GeForce GT 640 DDR3 is a small bit (approximately 13%) more effective at AF than the Radeon HD 7750. (explain)
Pixel RateIf using high levels of AA is important to you, then the GeForce GT 640 DDR3 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 max amount of data (counted in megabytes per second) that can be transported over the external memory interface in one second. The number is calculated by multiplying the card's bus width by its memory speed. If it uses DDR RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR 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 calculated by multiplying the total texture units of the card by the core speed of the chip. The higher the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to the local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.