Quote from Tresor:
Okay,
This Samsug has a dual link DVI connector as per this picture:
http://taiwan.cnet.com/review/lcd/0,2000089118,20066849,00.htm
and as per this despription:
http://www.preissuchmaschine.de/in-Monitor-Flatscreen/TFT-Wide-22-2/Samsung-SyncMaster-2343BW.html
So, the potential problem may only be a wrong graphics card.
Thanks for all your help.