Being that you are wanting PCI-X, I wouldn't expect anyone to have much advice for you. Nobody here uses PCI-X. We get the oddball(like yourself) that asks about it, but as it "died" back in 2005 or so when PCIe came out its rare to find someone actually expecting to use hardware that is that old. Usually those people figure out that their system performs poorly anyway and that the cost of more DDR2 RAM is often more expensive than buying newer stuff.