[lubuntu-users] Monitor Resolution Much Reduced on Lubuntu 16.04

[Aere Greenway]

Lubuntu Users:

One of my machines, running Lubuntu 16.04, has a monitor which has been 
working (as long as we can remember on 14.04, and a long time after 
upgrading to 16.04) at a resolution of 1680 x 1050 (or something like 
that).  And it still runs with that resolution on Windows 10.

For some reason, as far as we know, without us doing anything, when we 
boot Lubuntu, the resolution went down to 1024 x 768.

I suspect (but don't know for sure) this was caused by a system update.

In checking Preferences...Monitor Settings, the highest resolution 
listed is 1024 x 768.

I installed ARandR, and with that, the 1024 x 768 is again the highest 
resolution available.

We applied the latest updates, but that didn't change it.

We know the monitor currently works at the higher (1680 x 1050) 
resolution (on Windows), but see no way of configuring that resolution 
in Lubuntu.

Does anyone know how we can restore the higher resolution in Lubuntu 16.04?

-- 
Sincerely,
Aere