If you build an AMD rig, make sure you get a true 900-series chipset board, OTHER THAN one of the MSI 970A-G4x boards; they appear on a public Googledocs spreadsheet I am unable to link from work indicating that have weak VRMs that may pop under load. This will be less of a concern with a 95W CPU, the -G46 (which has heatsinks on its VRMs) may be acceptable, especially if you don't plan to overclock much, if at all.
For little more than a HD7750, get a HD7770. If budget limits you to the HD7750, make SURE it has GDDR5 on it; the DDR3 versions are slow abominations.
Edit: I agree with jas340 about going with an i3, since it provides a good CPU upgrade path (if you need it). H87 motherboards aren't too expensive.