Ok, I'm not sure this will help or not, but here goes:
Ypu may e able to creat a lower resolution that works beterr but is not available in game or for your monitor for that matter,
I wanted to change my resolution to a resolution that was not available in AC as it was not available or a resolution my monitor would accept so:
Using N Tune for Nvidia I went to the adbanced tab.
Manage custom resolution tabs
Check the "allow modes not exposed by the display"
Then in the custom resolution area you create the resolution you want. In order for it to save you must test it. If it doesn't work then try turning scaling off and try again.
You do NOT need to use this setting all the time. You basically create a resolution you can use if you choose. However the new resolution WILL be availabe in AC the next time you fire it up.
Hope it helps. I use 1320x768 in AC and 1680x1050 for everything else. I do this mostly for chat window...I can't stand the tiny UI at those resolutions.
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