Never mind, issue is sovled.
The Samsung HDD 103 SJ was undetectable for windows but all partition programs saw it as a broken disc.
I used the seagate tool and reinstalled windows on a cleaned disc. Now it recognises the disc again and i have normal acces to it.
what seagate tool? i thought you might have meant seatools and ran that, but it looks like it was just a testing utility (and it passed)
I used the seagate DiscWizard.
In the end, after it restarted again, the message popped up again.
I did the following things in this order to get it up and running againa:
I disconnected and reconnected everything, like a new built up (finally gave me a good reason to clean up some cables neatly inside)
Than i flipped the mobo battery for a few minutes.
Took out 1 RAM module.
Hooked it up, pressed the on switch for about 30 seconds and in the BIOS i disabled all HDD from booting.
It booted from the win7 CD and i could do a fresh install without any error at all.
Which of the actions was exactly the correct one i don't know and frankly i don't care either, it is up and running again and i was able to save my important data.
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