I have been running on two monitors for some time now, but have now acquired a third monitor. Windows detects the third monitor as a generic monitor (as opposed to Samsung xyz ...), but does not seem to output any video display to it.
Currently, my dual monitor setup is running both monitors off the 2 DVI ports of my video card.
My hardware:
Video card: XFX AMD Radeon HD 6770 Graphics Card (HD677XZNFC)
Motherboard: Asus P8Z77V LK Socket 1155 Intel Z77