Let me start by saying several days and hours of troubleshooting to discovery this solution. I'm hoping to saving others the time and trouble
1st PX1 is working.
( So this may not apply to all. But have noticed a lot of people reporting of PX1 hanging their system horrible hangs and getting frustrated to the point of RMA'n the card )
Scenario:
The most recent Windows update installed the latest PCH driver and all seemed well until installing the latest PX1 1.02 . This worked for a day and started black screens and crashing (that were actually systems hangs). After several restarts and not so wonderful win10 startup fixes, I went into safe mode and removed px1 and nvidia drivers did and clean install and unwittingly installed the same PCH driver. So more of the same and again back to safemode. I went back and reinstalled nvidia (PCH still) and system was running, then I went to the version 0.4.4 of Px1 that was working and ran fine but any adjustment would hang the system. So started troubleshooting cause I could at least restart without px1 starting at startup. I made a power target change "YAY" it worked added a voltage change it worked the a clock change it worked then a memory clock change HANG ending with a forced hard restart ...
Even the smallest change in memory clock 25 MHz would hang the system
The Fix:
I did a clean install of Nvidia 441.87 Standard and PX1 1.02 (This took 3 restarts cause a PCH driver have to be fully removed before standard can be installed!)
and it now works perfectly with every memory and clock adjustment available.
CARD:
EVGA RTX FTW3 2080TI
win10 Pro