Okay run these 2 commands in sequence .. and DO NOT reboot until you've run them BOTH:
sudo apt-get remove --purge xserver-xorg xserver-xorg-core xserver-xorg-video-intel xserver-xorg-video-vmware
then
sudo apt-get install --reinstall xserver-xorg-core-hwe-16.04 xserver-xorg-hwe-16.04 xserver-xorg-input-all-hwe-16.04 xserver-xorg-input-evdev-hwe-16.04 xserver-xorg-input-synaptics-hwe-16.04 xserver-xorg-input-wacom-hwe-16.04 xserver-xorg-video-all-hwe-16.04 xserver-xorg-video-amdgpu-hwe-16.04 xserver-xorg-video-ati-hwe-16.04 xserver-xorg-video-fbdev-hwe-16.04 xserver-xorg-video-intel-hwe-16.04 xserver-xorg-video-nouveau-hwe-16.04 xserver-xorg-video-qxl-hwe-16.04 xserver-xorg-video-radeon-hwe-16.04 xserver-xorg-video-vesa-hwe-16.04 xserver-xorg-video-vmware-hwe-16.04
Now running:
dpkg -l | grep "rc " | grep xserver-xorg
should return nothing.
If so, all done 
That did the trick. She now running like a Swiss watch. I called this one
SOLVED. Thank you so much. It was getting to the point where
PM7 was so unstable on this machine, it was basically unusable. Now, it's back to good ol' faithful and reliable
Peppermint 7. It great to know
Peppermint 8 will have this sorted out of the box - fantastic

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