[SOLVED] Proxmox 5.3-2 system clock slows to 50%

Johan T

New Member
Mar 22, 2019

I am a new user of Proxmox so I have no experience with any previous releases. I recently started installing Proxmox 5.3-2 onto a number (currently 3) of HP Elitedesk 800 G4 mini with Core i7-8700. It has been a pain free experience for the most part except for a strange problem that is present on two of the machines.The system clock runs at 30-50% speed of the real time clock (RTC/cmos). They were delivered with Windows 10 on them but none of them showed this issue before I installed Proxmox over them.

Apart from installing a clean Proxmox 5.3-2 system onto them I have only performed an apt-get update/upgrade cycle. On one machine I installed Chrony with the intent of having that machine serve as a stand-alone NTP server (the system has no internet connection). Since the issue is time-related I immediately suspected Chrony. But on one of the other machines I have the same issue and have not even performed an update/upgrade cycle yet. To summarise: Only one of the machines has not exhibited this behaviour at all. One of them has been intermittent and one has never stayed in sync.

All the kernel time parameters appear to be the same across the three machines. I will include some relevant system information below in the attached file.

Hopefully somebody can help me figure out what is going on.



  • sysinfo.txt
    3.1 KB · Views: 7
After a lot of reasearch into the inner workings of clock sources I finally disabled some power management features in BIOS; specifically Runtime Power Management and Extended Idle Power States. This allowed the machines to reliably select the TSC clock source during boot instead of HPET, which was giving me problems before. Perhaps it was also affected by the power saving features.

Hopefully this will be helpful to anyone else trying to install Proxmox on these HP machines.


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