Roamio Plus Rebooting

My Roamio Plus is rebooting many times a day. I replaced the HD and for a few days I had no problems. I plan on replacing the power supply next.

My questions are:
If the HD is the problem will Kickstart show the HD bad?
Can the power supply cause the HD to go bad?
When I replace the power supply if I still have a problem, what should I check next?

Thanks in advance,