This board does netinstall over ether1 but after that Ether1 becomes dead. Although lights are on and flashing not possible to send or receive any traffic.
In terminal port is up and running.

After log in through Ether2 everthing works fine but Ether1 shows as running and connected while no cable is attached!

Is this repairable?
How? Costs? Anybody has interest? I have more boards up for repair.

This board does netinstall over ether1 but after that Ether1 becomes dead. Although lights are on and flashing not possible to send or receive any traffic.
In terminal port is up and running.

After log in through Ether2 everthing works fine but Ether1 shows as running and connected while no cable is attached!

Is this repairable?
How? Costs? Anybody has interest? I have more boards up for repair.

First, make sure all the capacitors are good (not leaking, not swolled AT ALL). If they are leaking or swollen, replace them cheaply and easily.

Otherwise...

Sounds like lightning damage. You would have to find an exact PHY/chip replacement and then desolder/resolder... and hope that nothing else is also damaged. I would toss it and replace.

This board does netinstall over ether1 but after that Ether1 becomes dead. Although lights are on and flashing not possible to send or receive any traffic.
In terminal port is up and running.

After log in through Ether2 everthing works fine but Ether1 shows as running and connected while no cable is attached!

Is this repairable?
How? Costs? Anybody has interest? I have more boards up for repair.

First, make sure all the capacitors are good (not leaking, not swolled AT ALL). If they are leaking or swollen, replace them cheaply and easily.

Otherwise...

Sounds like lightning damage. You would have to find an exact PHY/chip replacement and then desolder/resolder... and hope that nothing else is also damaged. I would toss it and replace.

Well, I 'm a self educated network operator. Not an electronics engineer.... so I don't even have a clue what a capacitor is.....

Lightning damage is very unlikely. The last time we had a thunderstorm just coming near is 8 months ago and with ample lightning. Although I live in a country famous for them in our valley we rarely have thunderstorms.
I was more thinking of ESD? In the summer it is very dry here (creates high static energy in the air) and windy where in the afternoon usually a sea breeze comes in which is supposed to be loaded with ions.....?

This is also my suspicion in the many port flaps I still have with 5.8 in my network....

Search the forum here for leaking capacitors. You will find a lot of information regarding it.

There are many many posts (with pictures) regarding this. Many Mikrotik boards were built with fake-name capacitors (by accident), and thus many boards have gone bad. I've replaced caps on a few of mine, which have restored them 100%, and other people here have replaced tens or even hundreds of boards.

IF this is the problem, then anyone with any soldering skills can fix it in less than 10 minutes easy. I spent about $5 on new capacitors for mine.

Anyway, do some searching here for "capacitors" and you will get a good knowledge of this problem.