I am troubleshooting a Compaq evo D300v minitower computer. It has been giving the user non system disk errors with no disk in the drive. And sometimes it gives the blue screen of death after the message. Could this be a problem with the power supply, or some sort of hardware problem? It is running windows XP pro and has not had any trouble until now we have had these xomputers for three years and sometimes have problems with power surges and spikes.