It may not make a difference since your GPU is on the low-medium end. Worth a shot, though. You can do it real quick without changing voltages. I'd just be careful with a stock cooler on it.
...No offense, but that's kind of contradictory advice.
"It won't make a difference, but you can try it." Haha
My advice: Try the games first. If they don't run on the settings you want, then you can overclock. Get an aftermarket cooler to really bump up the speed.
I do realize that, but nowadays, overclocking your CPU is so damn easy, it'd be foolish not to. Not just for games, but everyday use. And I did say, it "may" not make a difference.
OP, 3.4 would be fine on the stock cooler. Just be sure to watch the temps and follow the proper procedures to overclock it.