u/Pretty-Fly-White-Guy

Hello Mac people,
I’ve been messing with my dad’s old iMac G3 and have been hearing a lot of noise (a short fizzle followed by some computer starting sounds) during the start up and shut down as well as an on and off grinding noise while it’s running. I’ve heard that these have dangerous voltage in the CRT, but I really don’t know anything about computers so I just wanted some outside advice before I continue.
Thanks