Updated firmware on both using Solidigm tool. They show the same standards now.
It's intel server. S2600CP MB. Now I remember (been awhile)
Basically, server got 16 SSD slots in front.
However, MB got only 6 SATA ports. 4 of them black and 2 white.
I have only 2 SATA3 plugs in right stack. And 4 SATA2 plugs in right rack on top.
Left rack is not even working (nor slots 3/4 in right rack)
Now all makes sense.
@CyklonDX, in topic about LSI raid controller, how all this would work together? Is there RAID controller with SATA ports which I can connect 2 SATA cables I have spares for my hot swaps upfront?