ESXI 6.5 restart

Hello All,

I have noticed that 2 of ESXI hosts regularly restarts at same time each week. The think is that on these hosts are only VM's with persistent disk and for auto refresh I have scheduled task twice a week and Wednesday and Saturday for example to be restarted at 12:00 AM and VM's get refreshed. Lately hosts started to restart at same time.

Here is the details about inventory:

ESXI 6.5 - 7388607

Horizon View 7.3.1

Windows 10 - 1709 with vGPU - NVIDIA

Around 30 VM's on each host.

Is it possible that hosts can be degradated because of the restart of 30-40 VM's at same time?

Thank you.