I assume the puter is not over clocked, right?
Reset the Cmos (check the pfd manual for instructions or remove the battery from the mother board for a minute or so and try again.
If it fails then when the puter acts up do not turn it off, remove the cover and do a wiggle test (shake gently all of the cables) ad see if there is a beep or the puter tries to reboot by itself again.
Mine has 2 Sata and 2 IDE, 4 HD 250GB each. Could not trash them that easily.