that seems a bit high, my comp would shutdown at like 63. Open it up, and use a can of compressed air to get rid of any dust bunnies that are crawlin around in there.
Ok, even with the case off, and a fan blowing into it, and it dusted, it still reboots. Im running an nVidia 5700LE. Even if it was overheating, why would it jus start overheating now? ALl my fans are running.