If you don't have enough thermal grease, the system will not boot or shut down after using it a while or when running excessive programs (like heavy games)
yeah I think I put very little... the annoying thing is that the manual doesn't say what amount or anything, so I couldn't tell whether it's too much or not... anyway the pc has been running for quite a while now. Can't install asus probe in Vista to find out the temps using windows...