Ok, you are going to have to clean and reappy the thermal paste on the cpu heatsink, I recomend using Artic silver
http://www.arcticsilver.com/as5.htm
follow thier instructions on the same site to clean and reapply.
If you follow these instructions and your cpu fan is connected to the correct place on the motherboard and the heatsink is tight then you will have no heat issue.
We must make sure the cpu is not over heating before we continue so please follow this advice and then post back