If your PC is overheating, go repair it.
Also, if it was at 85 Celsius, your computer would make an unwanted odor.
Don't lie please.
No igloo's here in NJ...should have said that was celsius. Thanks Kenmitch
So your going for the best overclock you can get within a safe temp with hyper-threading enabled? If so just try to keep it in the low 70's under severe stress testing and you should be OK. Might be able to push to about 3.8ghz or so depending on how much voltage she needs to stabalize.