There is ONE DirectX 11.1 card that my mobo will take as well. So I would at least have that for anything that required it. Hmmm....maybe I CAN make this rig work awhile longer.
Why do you say "one", like you don't have a choice? Assuming that the power supply is up to it, you should be able to install any PCI-Express-compatible video card. So far, all PCI-E standards are both backwards- and forwards- compatible.
The reason that I mention the power supply, is because that is the only effective limitation (subject to application bandwidth demands for GPGPU apps too, I suppose) on which video cards you can choose. PCI-E video cards, can draw so much from the graphics card slot, and then for more power, they may implement 6-pin or 8-pin PCI-E power connectors on-board. Generally-speaking, those connectors are not optional, if you want the system to boot.