If you go FM2, you have to realize that you have almost ZERO upgrade path. You're stuck on an Athlon or an A-series APU basically. If you don't plan on blowing the big bucks on the build later, then FM2 is fine. But if you want something you can periodically make better, I would go with a socket 1150 or AM3 build. My recommendation would be to make the graphics card a 7770, and use a G3420 Pentium CPU. You'll still get considerable gaming performance, and the choice to upgrade all the way to a 4770K if you'd like. However, keep in mind that the Z87 boards are the only ones you'll be able to overclock on. I'd recommend going with 1x4GB RAM for now, and then put in another identical 1x4GB stick later, when you save up some more money.
Regards,
Isaac