Power Mac G5 Dual 2 GHz freezing

I've got a dual 2 GHz G5 that has been freezing very frequently. About two weeks ago it started freezing up all the time. It doesn't always freeze while a task is at hand. I have installed a new HDD and installed a fresh copy of leopard on that new disk and it still freezes so I know it's not the HDD Recently upon entering the room that the mac is located in I have noticed a different odor. It is the the odor of burn electronics, but definitely a electronic smell different than what I am used to with my mac. I sniffed from the outside close to the cpus and noticed cohnsiderable heat and an intensification of said odor. Right now I am thinking that the odor and freezing issue is caused by my cpu(s) overheating. Does this make any logical sense. Is there any help you can offer. My thinking is that resetting the cpus could help.

I would strongly recommend that you get that Mac to an Apple technician el pronto. My initial thought is that the logic board is faulty, and something is cooking in there. Hopefully it's not major.