> I tried a pciex16 video card in pciex1 slot via a pciex1 to pciex16 adapter
> but the X5000 would not boot any of the combinations that I tried.

Thanks for the info.

> Primary Card in pcix16 slot X5000 would not boot even with just the adapter
> and no video card attached with the primary card in the pciex16 slot.

That's strange as such adapter should be just a dumb extension of the x1 connector (and the other lanes electrically dead or not even there).