Always 95°C. ;)
My theory based on testing is that PROCHOT# or the point where a processor starts to thermal throttle can vary by a degree or two from one processor to the next but TjMax is fixed for all E8400 CPUs. I realize that there are plenty of people that disagree with that statement but I haven't seen any testing yet to back up their theories.
JohnZS: I don't put too much faith in any software that tells me my processor is "Too hot" if it doesn't even know what the correct core temperature really is. OCCT obviously means well but it's using the wrong TjMax and is reporting the core temperature 10C too high just like Everest and CoreTemp do.
If you are Prime stable at 63C and don't plan to overclock any further then you're fine. Running as cool as possible improves stability but if you're already stable and happy with your overclock then temps aren't really important. Do you have any real world software that you run that gets your cores up anywhere near 63C? Most users don't. Prime is great for stability testing but is a little overkill compared to most gaming or video / music encoding a user ever does.
You can be Prime stable at over 90C if you're not overclocking too much and your processor won't start to thermal throttle and slow down until about 93C so at 63C you still have lots and lots of head room before you'll ever hurt anything.
http://img214.imageshack.us/img214/1381/test1smllf3.png