Compare any two graphics cards:
GeForce GT 640 DDR3 vs Radeon HD 6670 (OEM) 1GB
IntroThe GeForce GT 640 DDR3 makes use of a 28 nm design. nVidia has clocked the core frequency at 900 MHz. The DDR3 RAM works at a speed of 1782 MHz on this specific model. It features 384 SPUs along with 32 Texture Address Units and 16 Rasterization Operator Units.
Compare those specs 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 runs 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.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 6670 (OEM) 1GB is 12% quicker than the GeForce GT 640 DDR3 in general, due to its greater data rate. (explain)
Texel RateThe GeForce GT 640 DDR3 is quite a bit (approximately 50%) more effective at AF than the Radeon HD 6670 (OEM) 1GB. (explain)
Pixel RateThe GeForce GT 640 DDR3 is quite a bit (approximately 125%) faster with regards to full screen anti-aliasing than the Radeon HD 6670 (OEM) 1GB, and should be capable of handling higher 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: Bandwidth is the largest amount of information (in units of MB per second) that can be transferred across the external memory interface in a second. It's worked out by multiplying the card's interface width by its memory speed. If it uses DDR RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This number is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly write to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.