it was working fine and suddenly it stop working then i checked and i found the problem i guess it was a lightning or something like that the mini pic might be tosted and not the POE section.
Also the transformer died.
Any expericence like that?
any idea how to prevent that? or to protect mikrotik board and everything??

It seems your RB got high voltage spike ( more then 100V ) via POE or Jack.Do you have lightening in last time? Protection - use good grounding, surge protection for AC circuit ahead of AC/DC switching PSU and all shielded cables with shield connected to ground.

i had no protection , and also i found out the mini-pci card were tosted too.
what is the best to protect everything??

atmospheric protectos for the antenas? + rj45 protector too?

yes, it's the same chip with my RB that got lightning 3 months ago..

Actually this chip is just OVP. Possible your RB still life. Take metal tweezers and short this chip one side legs to other side legs. If your RB turn on and booting that mean you are lucky.