Considering the ease of overclocking 8 core FX "E" chips, the $100 for 8320E plus $50 for UD3P 2.0 board combo deal from Microcenter seems hard to beat for a cheap multicore workstation. You don't have to deal with used product worries. (I actually got my combo for $133.75 with tax when the board was on sale, lol.)
I would never invest in 45nm tech today. My i5 750 is a plain quad and it's a power pig when overclocked.
However, if your goal is to get past 4.5 GHz the UD3P 2.0 won't do. It throttles after that speed, regardless of temps, in Linpack. Cinebench multi shows improvement even at 5 GHz but stress testing isn't so simple with the throttling. Regardless, 4.4 or 4.5 on that board seems like it will run Fallout 4 just fine, looking at that chart.