I'd recommend checking out some of the new AMD Trinity processors. They have a lot of bang for the buck. I think you can get at least an i5 equivalent for a lot cheaper. Take a look at this site I found with a whole bunch of motherboards that will work well for your gaming.
This build will completely destroy those other builds. With a HD 7850, you'll be able to play just about any game out there on high settings at comfortable frame rates. If you need an optical drive, I suggest you salvage one from your old build to save money.
If you have any questions, feel free to ask. I hope this helps; good luck!