After update Windows 10 second monitor not Full HD, max 1600x1200. First monitor connected HDMI, second monitor VGA-DVI connector. Earlier 2 monitors view 1920x1080, a year ago i edited monitor.inf and it worked. System Radeon 7770, monitors Samsung LS24F350, windows 10 1903. I forgot how to edit and where is monitor.inf
What does Windows 10 Settings - Display show for resolutions for both monitors?
Do you have the latest Monitor drivers from the manufacturers?
Here is the latest AMD Driver for the HD 7770 from AMD Download page: https://www.amd.com/en/support/graphics/amd-radeon-hd/amd-radeon-hd-7000-series/amd-radeon-hd-7770-g...
Try updating the GPU driver if you don't have the latest.
I presume the DVI-VGA is an Active Adapter and not passive.
See if you can increase the 2nd Monitor using a small free program called Custom Resolution Utility (CRU).