Hey I recently took my desktop pc and put it into a tower case. It hasent worked since even though it did work before. It keeps telling me that there is no OS installed. The computer is an IBM so i dont have the XP disc from it because i got it used, although i have a dell XP disc which i successfully installed on my old laptop to make sure it works. Ive checked the cables but with no luck. Anyone know whats going on?