I have an nVidia Quadro NVS 450 installed in a Dell Optiron 380. Only DisplayPort #1 and DisplayPort #4 are detected by windows. The machine has a BIOS setting to automatically choose the primary video card, or to disable the primary when a PCI-e card is installed (which it is). Windows cannot see DisplayPort #2 and #3 no matter what I do. I have tried the Windows Drivers, latest nVidia Drivers - no dice.
I am assured that this video card cannot break in this way.
I'm plum out of ideas. I've tried reseating the video card. I've contacted Dell and they've remoted in and looked around - threw their arms up after two hours.
I'm running Windows 7 64-bit. All four monitors are 1600x1200 Dell monitors.