|Are you trying to install these as a matched pair? Because if you are it most definately will not work.|
SLI requires not only matching cards but matching protocols as well along with an interconnection cable.
If you are trying to install as a single video graphics card then you must set the BIOS to search for the card to start it...
a) PCI-e card must use the x1 slot and not secretly as it is designed for that...totally different protocol than PCI.... BIOS must be selected for PCI-e video adapter
b) PCI video adapter must use the PCI protocol and the BIOS must be set for that video adapter.
Do not rely on Microsoft for any drivers for the Video Adapters as more than likely they will be out of date. Go to the Video Adapter manufaturer web site and download the driver from there for which ever card you use.
The operating system does not dictate as to what video card is used...That is determined by the motherboard and RAM that is being used....and again dependent upon the basic socket design built into the motherboard as
all of which are different sockets and form factor although the motherboard may have the capabilities of using any of the 3. The BIOS must be set to the correct one so it can be detected properly upon boot!
Change Is Good