I have installed Precision X 16 5.2.7 and configuration correctly for me.
When the system is starting 3 icons are loaded in taskbar before of start of Precision X. The icons are static.
When Precision X is loaded has 6 icons being 3 statics loaded before of Precision X and 3 corrects.
If mouse pointer pass above of 3 statics icons they are removed.
Image 1 is the icons before Precision startup.
Image 2 is the 3 statics icons more Precision X icons.
Image 3 show just Precision X icons before mouse pointer pass above of statics icons.
The selected icons are GPU clock, usage and temperature.
I have used utilities to clean taskbar icons after of that issue, but the problem continue.
Thanks for reply and an Good year for you.

Installed over previous version and clean install has the same issue.
Thanks for your reply.
Good luck.

this is an old thread so it maybe that the answer has been given else where, but from my investigation it is from graph selection screen on the precision x UI itself. Underneath the test button, if selected it will allow you to choose what data to monitor and where.
 
When I clicked the GPU1 under "show in OSD" it added the second tray icon indicating power, which is the first of many items to monitor in the drop down available data to monitor. 
 
seems to have worked for me, can't say it will for everyone. I didn't have any luck with the Scheduler.