Some of them will support two devices. Being that there are two video cards installed, perhaps one of them is capable of running two. What are the make and model numbers of the installed cards?
Just installed a PCI based video card in my older desktop so that I can run dual monitors (one's on a serial port, the other is DVI). I'm wondering if there is anyway to ALSO use the OEM/stock video chipset to run a third monitor at the same time on the original serial port?
We're using windows 7 here, if that helps.