Thanks David,
But your card was modified by a friend who is much better with R400 cards than I am (although I do mod R200 and R300 cards).
The difference between the 2.5 Quad and the 2.7 isn't great enough to justify the change by itself.
And the X800XT performs pretty close to the X1900GT.
Also, with the PCI-X models we have access to the all the supported PCI cards (like the SB Live, USB 2.0 cards, SCSI cards, etc.).
However, should they start creating video card drivers with bios emulation support, we might eventually see PCI-e cards supported beyond the 1900GT (big might folks, don't even ask the developers about this speculation).
But think about it, a Quad-core 2.5 G5 with an HD4670 card (or better).