Ok, newbie here, ( I know enuf to TB dangerous), wanting to get a little more out of my 7 yo 690 workstation, bought a Zotac Geoforce GT740 PCI-express card (2GB), and found that I had not 1, but 2 NVIDIA 285 cards (only 128mb video RAM ea.), mounted on a riser (plugged into the PCIe 16 slot). So question; since the external connection slots (back of computer) are "higher) than the PCI-X slots (to match the additional height of the video riser) can I just pop the new card into 1 of the 2 PCI-e slots (on the riser)? (or will the system insist on seeing 2 cards?). Windows 7 x64 HomePremium. Pretty sure they are not SLI configured.