Thanks for the reply!

So what would have caused the computer to shut down while it was running? I realize getting accurate information on what happened from someone who is even less knowlegable than me is hard. Why would putting the hard drive in another computer have the same problem? Why, when I put the original hard drive back in the computer that worked cause the same shutdown problem? And how do I get the updated drivers for the motherboard say if I put them on a flash drive to run on the problem computer which won't start in safe mode or any other mode? Could it be a virus?

Have a wonderful day!