But the problem is that one card of one of S3's is not working at all!
I have checked everything power, cabling, anything I can imagine but it persist and not working at all!
Any ideas what should I do?
Did you try moving the cables to the other ports?
Otherwise, I would open it up and look for any loose connections. Sometimes things get knocked loose during shipping.
Yes, tried it and open it up as well but found no problem yet!
Checked the controller cable, changed it with the other one! But absolutely nothing happened yet!
What happens if you connect the cables from your PSU that worked with the 'good' unit just to the 'bad' unit? (checking the possibility that there is some issue in your PSU or its cables)