A mate of mine has a PC of 18 months, a HP dv 9700 entertainment centre which has decided to trash itself.
After turning on one day it then decided to turn itself off, and stayed off.
I had a look and managed to explore the dos and it put a message up that read TPM failure.
Thats Trusted Platform Module failure.
Apparently its a piece of software that HP install to only allow certain software to be run on it.
HP dont want to know about the issue .
An otherwise perfectly good computer has been trashed by a piece of software that offers no benefit to the owner, only to HP.
I suppose the moral is dont buy a HP PC, you'll be sorry