Tried removing the update to no avail.
Tried messing with settings in-game and in Nvidia control panel (Asus 1080) to no avail.
Not really a computer whizz, so I'm in the dark here guys.
Help!
EDIT:
Found it!
Geforce Experience needed an update as well. Hadn't done so by itself, but all is well again.
2. Edit:
Damn! The tearing is back again today... God I hate Windows updates...

3. Edit:
Right.
So after Windows Creators update I can no longer have multiple screens.
And it's not enough to turn one of them off either.
No, I have to disconnect one or the other physically or I get screen tearing on either screen. It's more pronounced in some games than others, and Elite: Dangerous takes the biscuit.
I suppose those with multiple identical G-sync screens won't have this issue. But it's a no go for a PC/TV setup like mine.
Thank you Windows 10 creators update.