That's a Dell card and some links say it can support 2 monitors but in mirrored mode, meaning the same thing would be on both screens. You need a DVI splitter to do that. You could try using a display port to one and DVI to another but I still see it acting as a mirrored display. I'm not positive since the card is so old, but Windows 10 may allow for it to be made into an "extended" display where you could have a video on one screen and something going on the other but just as one big display, like picture in picture type thing.
To have 2 true desktop displays, you need a different card.
"It worked before you broke it!"