You should be able to play at 1280x720, probably on medium or even higher in a lot of games (but not the latest).
If you have room in your budget for it, check out a GDDR5 version of the HD7750 instead; they're not much more expensive. I have used that card (although with a faster CPU) to play GW2 at 1600x900 on a mix of medium and high settings.