"The GeForce GTX 560 is a strange GPU, in the sense that its manufacturer, NVIDIA, doesn't set default clock rates for it. Therefore, it is up to the video card manufacturer to decide which clocks to use. The GeForce GTX 560 Multiview from Zotac works internally at 820 MHz, accesses memory at 4 GHz through a 256-bit interface, and has its processing engines working at 1,640 MHz - the same clock rates used on the standard GeForce GTX 560 Ti. The only difference between the two is the number of shader engines (336 vs. 384 on the Ti version). The Multiview model from Zotac allows you to connect up to three video monitors, a feature not available on regular models."
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