Windows

I am stumped on this laptop that keeps shutting down, first I was told it wouldn't let user log in, when I tried, it kept powering down before even getting to the log in screen. One attempt, it shot up a quick messages about a power setting, that it was automatically fixing. (too quick to read)Then it continued to shut down, tried with and w/o battery, on battery only. It won't stay on long enought to access the bios or anything. Suggestions?