kfmk wrote:
Using a VGA adapter for my mid-2011 27" iMac running High Sierra I hooked up a 27" LG external monitor. Everything on the external monitor is blown up way to big and I haven't found a way to normalize the sizing on it. This prevents me from using the display well - it might as well be a 4" X 6" display. Thanks for any help.
How old is that VGA adapter? There was a time when those would limit the resolution, or set the max resolution of the monitor. Current VGA adapters might be able to support 1080, but some older ones may actually set it to something like 640x480, or they may have had DIP switches on them to allow you to change them. Software settings would have no effect on the VGA adapter hardware setting, if that might be an older VGA adapter you pulled from a box in your closet. Have you ever used that same particular monitor and that particular VGA adapter with any other computer at 1080 resolution in the past?
What happens when you use the HDMI cable? I have an even older 2010 iMac and use the HDMI adapter to connect to a 1080 TV set just fine.
If you plan to go to the Apple Store anyway, take that monitor with you and ask them to help you get the right video adapter cable and connect it to a floor model Mac to make sure it works, maybe?