There are several possible causes for that freezing, the following are some of them:
1) HDD/SSD is defective.
2) Malware (some kind of virus/worm)
3 ) RAM or CPU is defective
4) An application/software
5) Buggy updates
I recommend that you download
Malwarebytes (
Malware Protection for Home | Malwarebytes), boot into
Safe Mode WITHOUT NETWORKING (as in the video tutorial following the link below) and
scan your computer. But before installing Malwarebytes, while the computer is in
Safe Mode, notice if it does freeze as before. Please come back and let us know.
BOOT INTO SAFE MODE TUTORIAL:
Boot into Safe Mode