Thanks for the responses.
Suztera :
It can run two monitors yes for browsing and casual uses. But for gaming on two monitors, it is not recommended.
What R9 270 or R9 270X are you looking at? some have different outputs from others.
Small ones!
XFX 270 and 270x cards with Display Port : 1, DL-DVI-D : 1, DL-DVI-I : 1, HDMI : 1
powercolor 270 1x DVI + 1x DP + 1x HDMI
MSI 270x Mini DisplayPort x 2, HDMI x 1 (version 1.4a), Dual-link DVI-I x 1
KiloWolf :
Depending on what you are doing then yes. Some games will lag you out but some games will not. But if you run into lag problems caused by running two screens then just do not use the second screen for the game. I use my second screen to keep track of things while I use the first to game.
That's pretty much what I have in mind, I've single monitored since I stepped up to 24" but it's always good to have a holding pen for spare windows to one side. I thought about 2560x1440, but I'm wondering if 2 1920x1200 screens don't make more sense.