Installing a PCI video card in xserve (early 2008 quad 2.8 Xeon)

Hi,

I have been having a great deal of difficulty getting video card to work in a 2008 apple xserve running 10.7.4, I'm really hoping someone here might be able to help. I have tried a couple now and am trying a NVIDEA GeForce GT120.

A discussion here suggested that the Geforce 120 would be a good match. The card I have has come out of a mac and is definately mac compatible. Apparently the pci slots can only handle up to 25w but can't seem to see the 120 GT in any of the power consumption charts.

When I check 'About this Mac' -> more info it is not showing up under PCI slots, I've tried installing it in either slot but to no avail. Is there something I need to do to make the xserve realise it has a new card? Should I remove the small standard card?

Any help would be very much appreciated!

cheers Alex