The i3 setup is alot better. The G630 is a pentium at 2.7GHz where as the core i3 2120 is at 3.3GHz. Also the core i series have a much better, faster architechture than the pentiums. Pentiums are no good for gaming.
@Outlander_04 --- I share the exact sentiment. The only thing that is really hard is the fact that you cannot just go out and test this as unlike TV's wherein you can see and inspect before you buy, the result of a build is more theoretical.