Voltages are all stable and within normal range. (Both machines)
As far as windows reinstall, I did do a full reformat of my hard drive and installed all drivers and applications from scratch after these problems started. It fixed the problem until I turned my machine off last night, then reappeared when I restarted my system this morning. Everything works perfectly except for games.
BTW, I'm one of those people that regularly reinstalls windows about every 3 months or so.