Try 1 AGP and 4 PCI, each driving 2 displays in one system.

And to the original poster... Not all system BIOSes play nice with certain confirgurations of graphics cards. Not all graphics card drivers play nice together either.

If you need a recommendation on a new PCI card though: ATI Radeon VE. It's currently our lowest end chip, but it's more than adequate for a PCI bus card and to drive a third monitor. The plus: it will also drive a fourth monitor if you want to add one later (or TV).

Bruno