I'm new here, but have had MSFS for a few years and have been on a few MSFS forums. I have heard nothing but "WARNING!" when it comes to overclocking. For every guy out there that says he has no problems, there seems to be two or three that have cooked their CPUs.
Avsim has a nice tweak (maybe here too....?) to take advantage of Pentium's HT technology.....I would suggest that tweak before putting your CPU at risk by overclocking.......unless you have disposable funds.
Good luck!