Question Acer Predator XB271HU suddenly capping at 85hz - please help!

Jan 2, 2021
I'm having a very frustrating problem where this display will no longer go above 85hz. It worked absolutely fine since 2017 when I purchased it. This issue arose when I unplugged my second monitor (not the predator) and plugged it back in a week later. I did not use the Predator during that time, but yesterday when I turned both it and my second monitor back on, the Predator was capped at 85hz. I should mention that when I unplugged my second monitor I also unplugged the keyboard. Both are plugged back in. There appear to be no other issues.

I'm fairly tech literate, and I've looked at other posts with people having this issue. It's almost always the DP cable. In this case, I know it's not that, as I will detail below.
I've tried everything I can think.

-Checked settings in Windows and NVIDIA control panel. Both give me 23hz, 24hz, 59hz, 60hz, and 85hz. I believe normally I am able to select 100hz, 120hz, and 144hz as well with this panel (and 165hz if I OC). I cannot currently select anything above 85hz.
-New DP cable (reputable brand) did not work. This cable DOES work for 144hz on another display I own. It is important to mention that I have both a gaming laptop and tower. Connecting either to this display results in an 85hz cap. I have three different cables I've tried, same result. Again, those cables DO work on another 144hz 1080p monitor I have.
-Updated NVIDIA drivers. I'm on a GTX 1080.
-Power cycled, also unplugged all cables for 10 minutes or so and restarted.
-Tried different DP out's on my GPU, same result.
-Tried different computer, same result.
-Disabled fast boot (seems unrelated - supposedly related to USB issues, but it worked for someone so I tried it).
-Unplugged all USB hardware other than mouse, same issue. Unplugged mouse and plugged into a different port, same issue.

It appears to me that the monitor is the problem as I have tried several different cables that all work with another computer. It doesn't make sense to if that is the case, since the problem started when I messed with my other monitor, but it appears to be a coincidence. I'm hoping someone has insight and that the monitor isn't going out. Like I said, there is zero indication of anything wrong other than the hz being capped. Otherwise it's a flawless panel. I don't even have the backlight bleed on this panel that most others have had.

Thanks in advance!