P2715Q, no signal without repeated unplug or reboot

I realize this is an older display but have an interesting issue. We have had lots of these displays for years, but this is the first time seeing this issue.

In order to get an image, the P2715Q requires either a quick unplug or quick PC reboot every single time. It seems like it needs a soft wake-up to function.

I have found two workarounds that I'd like to avoid:

1) First time I turn on the PC = after a few seconds, the monitor shows "entering power save mode," and stays dark. I force shutdown the PC (using its power button) and immediately turn it on again. Now, the display shows an image from the start - bios, login, etc.

2) I quickly unplug and replug the monitor then turn on the PC for the first time. Same thing - display shows an image from the start.

The fact that the display works consistently using either of these workarounds tells me that there is nothing defective with the hardware. I have unplugged everything from the monitor and held down the power button for 30s to reset the monitor many times with no luck - I still need to use a workaround.

Does anyone have any ideas?

The monitor is the sole monitor, and there is nothing else plugged into it besides the video and power cables. The unit is set to output 4K resolution at 60Hz. MST is "off" per the menu. I am using a USB-C (GPU) to DP cable (monitor).

This is only happening on a brand new PC with an AMD 6900 XT GPU. When I connect this monitor to a MacBook Pro, there's no issue at all. It works just fine with no workaround needed.