Computer randomly shuts itself down.

Local temp is not the same as computer temp. There are many things to check...one, make sure that your computer isn't in an area where it has bad airflow. Give it room to breathe. Two, check the fans. If they're clogged, the fan will do absolutely nothing to cool your system. Three, make sure when you do a scan you don't set it to auto-shutdown after the scan is done.

Let me know, I'll help you from there.