jesus. these processors will not run modern games. you can get an entire rig for 600 bucks. why not get the APUs or a core series cpu
Incorrect. My rig posts 64.7 FPS in uniengine heaven 1920x1080 @ 4xMSAA, 4xAF with an overclocked x3 455. The games I play (borderlands 2, Metro 2033, deus ex) average 50-60 fps with the same settings (DoF off, of course).
To the OP; pacioli's solution requires the least amount of work. the G630 will also give you a longer upgrade path. If you think you'll want to replace the processor in the next year or so, and you don't want to mess with overclocking, go with the pentium.
If you plan on keeping the processor for longer than a year *and* you are willing to overclock, the x3 will give you better performance right now.