Hi again! :)
It seems like it didn't work. I got another blue screen again:
Problem signature
Problem Event Name: BlueScreen
Code: 133
Parameter 1: 0
Parameter 2: 501
Parameter 3: 500
Parameter 4: fffff80064afb320
OS version: 10_0_19041
Service Pack: 0_0
Product: 256_1
OS Version: 10.0.19041.2.0.0.256.48
Locale ID: 8192
Extra information about the problem
Bucket ID: 0x133_DPC_NETIO!PplGenericAllocateFunction
https://1drv.ms/u/s!ArNoV6IlyN9DhuVbQctTlHu1SdEgEQ?e=3uYCLX
So it worked perfectly till today. Another thing is, that I updated my nVidia drivers yesterday. I don't know, if this is a possible cause, but I will try to do a clean install.
Best regards and thank you for your answers. :)