[FIXED]Desktop icons keep rearranging after monitor sleep
After a bit of researching I figured out that the issue lies how Windows handles the DisplayPort interface.
Whenever the monitor powers off and the DisplayPort DDC link disconnects, Windows switches to "simulated" monitor with a default resolution. In my case this default resolution was set to some odd value; therefore rearranging every icon on the desktop to the upper left corner.
To find out what exactly the "simulated" monitor is, I turned off the monitor and used SysInternals Process Monitor to find out what registry path Windows was accessing.
Found the last path Windows accessed before the monitor powers on again, and in my case it was:
HKLM\SYSTEM\CurrentControlSet\Control\GraphicsDrivers\Configuration\ACI28A3149242_27_07DF_9F^9B5BB1CAE0B279C3217B8F8B0ADC8E00
Under that path was a tree called "00" with two keys which are:
PrimSurfSize.cx
PrimSurfSize.cy
Under "00" was another branch also called "00" with five keys which are:
ActiveSize.cx
ActiveSize.cy
DwmClipBox.right
PrimSurfSize.cx
PrimSurfSize.cy
These keys above were set to values either 1920 or 1080, so it seemed that Windows was setting the resolution to 1920x180 while the monitor powers off (don't know why).
I changed each 1920 value to 3840, 1080 to 2160, and the problem was solved.