Intel I5-4430 vs G3258 OC

[MaxBouff1224]

Hi!! I would lile to have your advices and solutions.

This is my current setup:
-Intel I5-4430 3.0Ghz with turbo mode 3.2Ghz
-Gigabyte GA-B85M-D3H
-Gtx 650
-8Gb Ram Ddr3 1600Mhz
-Windows 10 Pro x64
-Dolphin 5.0

I play with a lot of setting and i always have small bug, lag or audio crack.
Can you give me the optimal configuration for my setup ?

If i buy a Pentium G3258 with Cooler Master and overclock it at 4.2Ghz (not 4.5Ghz
because i think my cpu max voltage is 1.2) can i have more quality and no problem ?
It's a good solution or my current pc is okay ?

Thanks !!!