The hub was changed and the unit worked for 5 min  

The unit restarted without notice severeal times (the unit was on a ups 3000kva) interval >30s-5min<
It restarted even if the cgminer was stoped
The Ac is set to 16 C  (input senzor temp =14 C output max 41)
i`ve changed one power supply  with the only one i had 1200 quadro antec (had to do some modifications )
firmware 225  (tried also  320 but the cgminer will not start)
added 2 fans at the output temp constant 39 
difficulty set to >64
Thorvald
luck factor -50%   : 
