Logic Board Failure?

[ASecretCherie]

My first generation white macbook had a fall and became totally unresponsive. The screen would flash on, but stay black and the drives would whirl on but nothing would happen. I took it to a Mac Authorized retailer (I live in Germany, no Apple Stores) and they said it was the logic board and they wouldn't fix it. (It is no longer in AppleCare.)
I later noticed that they hadn't even opened the case, so I don't know what kind of diagnostic they ran.
I decided to open it myself and see if I couldn't somehow bring it back to life. With directions from ifixit, I removed the logic board, cleaned it and put it back in. No change.
Later I found a cheap compatible logic board on ebay (it claimed to have a defective battery connector but otherwise functional). I put it in and it was the exact same non-functional condition.
Were both logic boards totally non-functional and in the exact same way (to quote Lebowski, did I exchange a ringer for a ringer) or is there some other problem that makes the macbook completely useless?
Thanks in advance for your help. I really love to see this machine brought back from the dead.
(And if it's relevant, when the macbook first failed, I removed the hard drive and was only able with much difficulty to get it to mount and to repair it. But once I did, it went back in the Macbook and nothing changed.)

 

[Corrosive vinyl]

I don't know about macbooks, but had apple replace a logic board on my ibook years ago. This was at an apple store that they told me so totally different situation.

I would recommend going back to the place that tested it and ask them what they did or show you what they did. Do you have the hardware disks that came with the macbook? you could do a hardware test with those cds I think.