Hey. I have a radeon HD 7850 oc version from GIGABYTE. I am thinking about getting a 2nd 23 inch 1920x1080 monitor. Would one of these run it smoothly? Or would I need a second? Or would it be better to buy a whole new card?
Depends on the games you play. For some less demanding games, you should be fine running a 2nd monitor.
One thing to note, 2 monitors stink for gaming. For instance, FPS games, your crosshairs are at the bezel...
If you are using it for RTS, then it should be fine but I think every RTS have lower graphics requirements so you wouldn't need a second card.
Anyways, my idea is to buy the monitor, see if you can do it with 1 card, and if not buy the second one later. My gut is telling me you won't need a second card since for FPS games, you'd need either 1 or 3 monitors.