Alarm sounding when laptop is turned off

I was streaming video when the screen became pixelized & snowy. It wouldn't respond to the mouse or the keyboard. I did a hard shutdown and plugged in the power supply. After it was plugged in for a bit, I tried to boot it with no results until the alarm started sounding. The alarm sounded for several minutes but no other indication that the computer was working. The alarm has since stopped sounding and I've tried to turn it on but it's not responding at all now.