Some users have recently had their accounts hijacked. It seems that the now defunct EVGA forums might have compromised your password there and seems many are using the same PW here. We would suggest you UPDATE YOUR PASSWORD and TURN ON 2FA for your account here to further secure it. None of the compromised accounts had 2FA turned on.
Once you have enabled 2FA, your account will be updated soon to show a badge, letting other members know that you use 2FA to protect your account. This should be beneficial for everyone that uses FSFT.
My CPU usually idles at about 84-86, but I let F@H run over night, and it was close to 120. Is this common? Is this hurtful? Should I get some more fans?
i don't think that sounds way off. More fans are always helpful. Another thing is a new heatsink. One guy that lived on my floor at school was folding with his 2.8c stock heatsink and speed and his started hitting like 140-160F we got him a thermalright heatsink with the heatpipes and now it never goes about like 105F with folding running 24/7
Heatsink is like$50 that is only bad thing. The same company makes some that look just like it for around 30-40 without heatpipe technology, but they are still all copper.
My Athlon64 runs 118-120, slightly more with the door to the CPU hutch closed, but it hasn't hurt it at all. Your temps are well under spec, so don't worry about it.