Boards are fundraising to help the people of Ukraine via the Red Cross at this horrific time. Please donate and share if you can, you will find the link here. Many thanks.
Try holding the Power Button for 3 seconds. If you do have to pull the plug, do it quickly to prevent it from arcing.
a mate had Blackblaze and whenever Safety Freeze kicked in, it would lock his entire PC (its not meant to do this apparently). There is a way through blackblaze to see what folder/file caused the safety freeze (if it was that).