HP Z840 power kernel 41 error

[M_Architect]

Dear Community! I wanted to share my experience with a HP Z840 workstation, problems and solutions. Just in case somebody is or will be struggling with such setup.

A got a used HP Z840 with two E5 2643 v4, 64GB ram and a Quadro M5000. I upgraded it with two brand new SAS drives (raid1) and a 512gb HP Z Turbo Drive g2.

Fresh installation of Windows 10 and all drivers from the HP drivers page. Everything was working ok, but then I noticed some software had some "not responding" problems, which seemed to be connected with the graphics drivers. I therefor got the latest production branch nvidia drivers. After rebooting a new problem was present - with every reboot or fresh start the computer started booting, hanged, rebooted by itself and then booted again slowly with success into windows. Now all software was running without the previous problems, but this reboot problem was present with every new start or reboot showing as a critical error (power kernel 41) in Event Viewer. After changing the graphic drivers to the older HP recommended version the reboot problem got solved, but again I was left with some "not responding" applications.

The solution: I adjusted UEFI Settings and upgraded the Quadro firmware AND disabled the Nvidia audio driver. I guess disabling the Nvidia audio drivers, which I don't need as the workstation has another audio source, was crucial for this solution. Before disabling this driver the power kernel error was still present.

I haven't had the chance to test this through, but for now it seems all problems are solved and the workstation is running without any problems even with the latest production branch graphic drivers.

Does anybody have this kind of problems on a Z840 and if you do, what was the best solution for solving them?