Vm fault pager read error

It is me again. I keep using the NomadBSD heavily.
New bummer.
I tested on PC with 32Gb ram no issues.
laptop with 8 Gb ram no issues.
But two laptops with 3 and 4 Gb ram die with a black screen.
I can see a lot of errors in console “vm fault pager read error”
I just run jar application with the command
java -jar file.jar

I use openjdk8
as I sad no problem with 8Gb ram and more machines.

Sounds like bad ram.