There are some good links in these threads:
https://forums.totalwar.org/vb/showthread.php?t=77594
https://forums.totalwar.org/vb/showthread.php?t=67094

The dangers, of course, are fried chips. Cooling is probably the most important factor, if your case isn't properly ventilated, your system will be unstable at best. Some CPUs/MoBos are friendlier to overclockers.

I'm not really sure it's worth it these days, but I haven't really been following the tech. I'm looking at getting a water-cooled system, but mostly for the reduced noise. As the system ages, I may overclock it to slow down it's inevitable trip to obsolesence.