@apz No, I have not done any such customizations.
@olivierlambert Tried with tsc clock, same result. rngd started to eat 50-100% of cpu right after started it,
However I just tested how Oracle runs if the rngd service is stopped....and looks like no problems.
So the solution seems to be just stop and disable the rngd service and everything works the same they did in bare bone hardware!
Thanks to everyone who helped with this!