I'll take a look if the problem persists thanks. I found a thread on a linux mint forum that said if you add this line to you xorg.conf file it eliminates the screen tearing instantly. I tried it and it works perfectly.
The default is : Option "metamodes" "nvidia-auto-select +0+0
Change to : Option "metamodes" "nvidia-auto-select +0+0 { ForceFullCompositionPipeline = On }"
I'ts the only thing I could find at he time to stop the screen tearing. But will try the compton fix you suggeted also.