I'm starting to notice this too as of today.  I've restarted my PC a couple of times and no avail.  OSD is not popping up.  I mainly game with DX11 titles anyhow.  I recently upgraded my whole rig and ditched XOC for X1.  Initially, X1 was working as intended. All my GTX 1080 Ti FTW3 fans spin and profiles are saved.  However, the OSD is still finicky.  Sometimes it works, other times, it doesn't.  I can't help but feel disappointed and frustrated.  I don't run a lot of background processes and the only other apps I use are Adobe CC programs for work.  Is there anyone out there who has some knowledge on this mess?  Perhaps someone from EVGA can chime in.  I feel it's been far too long for this bug (Is it even a bug at this point?) to be ongoing.

turbochargedazn
Same here as well using the latest 3.19.0 Version. Initially the first few days of using OSD in Final Fantasy XIV it worked fine. Now today I start up the game and the OSD is missing. Tried force closing it and double checking PX1 settings to no avail. Pretty much it works whenever it wants to work. Also tried running the game in both Borderless fullscreen and Fullscreen mode and nothing seems to work.

Same here Turbo.  I'm having the exact same issue however, my GPUs are also running super hot in FFXIV alone. I have no idea why it doesn't make any sense to me.  The game itself is not very GPU intensive.  I keep coming back to this board and checking up on other people's issues or solutions.  I've even gone so far as to do a full system wipe and reinstall everything from scratch and the OSD issue is still persistent.