Had that happen to me 4 times and only 1 time it was the browser and flash not being compatable....had to roll both of them back to older version..
one time it was a firewall needed updating(ZoneAlarm)
another time it was a CPU running hot...
the last time it was a windows "autoupdate" bug...if you still use XP or win7, there is a bug in the update program that maxes out your CPU...easy to fix with a free program called "process explorer"...you will know if that is it by bringing up your task manager, if the CPU is running at 50% while idling that is your problem...
https://www.cnet.com/news/using-process-explorer-to-tame-svchost-exe-advanced-topics/
I always keep all auto updates turned off until I get some feedback on a new update.