Hello DanielKuzmin.
Your crash dumps are not showing any finite probable cause. In such a situation, it is better to enable
Driver Verifier to monitor the
drivers.
Driver Verifier - Enable and Disable
Run Driver Verifier for 24 hours or the occurrence of the next crash, whichever is earlier.

Information
Why Driver Verifier:
It puts a stress on the drivers, ans so it makes the unstable drivers crash. Hopefully the driver that crashes is recorded in the memory dump.
How Can we know that DV is enabled:
It will make the system bit of slow, laggy.

Warning
Before enabling DV, make it sure that you have earlier System restore points made in your computer. You can check it easily by using
CCleaner looking at Tools > System Restore.
If there is no points,
make a System Restore Point manually before enabling DV.

Tip
Test your RAM modules for possible errors.
How to Test and Diagnose RAM Issues with Memtest86+
Run memtest for at least 8 passes, preferably overnight.
Let us know the results, with the subsequent crash dumps, if any.