Two non sli graphics cards in a specific motherboard possible?

Hi I'm on a asus p7h55-m/usb3 motherboard. And I'm about to upgrade the graphics card, from an nvidia gtx 450 to a gtx 770 (4gb). I do a fair bit of colour grading and they recommend using two graphics cards, the weaker dealing with the GUI. I'm wondering whether I can install both the new and old card in the motherboard? Primarily using the new one, but in specific program's using the older card to deal with those tasks. I'm using davinci resolve.

I know the p7h55 doesn't support SLI but is it possible to have two cards not functioning in sli?