How would you monetize...

... a site that offers PC help and fixes for certain problems (such as viruses, etc.) ?

You could integrate a shop with all kind of keys for antiviruses and windows and other software products. Also advertise PC part with amazon affiliate or any other pc part shop. You could make reviews for different products and this way you can expand to YT. You can sell your own software that you make to solve some typical problems or IDK. AdSense?

One of my first sites was for local PC help. Phone calls came in daily to fix some idiots computer in my city.
Collect leads and sell them to a local IT tech.
Most anti virus programs have an affiliate program.

OP check onenetworkdirect affiliate network.