Interesting enough, it never seems to amaze me how much nothing changes. Over the years I have run into enough hair pulling experiences with laptops that can fill at least a small volume. Anyway, in this situation I was on a goal to reinstall Windows 7 Professional on three Dell Vostro laptops. As we know if have been doing this for a while, the OEMs often put an OEM partition on their products. These partitions usually can be removed if you reinstall the OS without using their recovery procedure. I have done this many times.
In this case I installed the OS on all three laptops. When I did the first one, I left the OEM partition because at first I did not think to wipe it. After the OS was installed I went back and deleted it with Diskpart. All was OK but for a small un-formatted partition at the beginning of the drive.
When I did the second two, I thought delete it while installing and you will not have to do it later. Well, I don't know why it happened, and I don't know if it is why it happened, but after I was done I noticed that these two never shutdown no matter what: Shutdown button, power switch, or command. They just restarted automatically.
My solution was more of a gut feeling from dealing with these goofy problems. What I did was download the BIOS utility and re-flashed the BIOS. Now the BIOS was the same rev; but it worked.
Why did I think of re-flashing? It came from so many times, sometimes in the dead of night with failing servers and PCs where magically a BIOS or Firmware update fixed the strangest problems and resurrected dead machines. Might not always work, but it has more often than not.