Well the board D946GZIS has the following:
Intel 82946GZ MCH;
Intel 82801GB ICH7
LAN: Intel 82562G Platform LAN Connect 10/100 Sound: SigmaTel STAC9227 Graphics: Intel GMA 3000
And the new board DG41TY has:
Intel 82G41 MCH;
Intel 82801G ICH7
LAN: Realtek RTL8111D Gigabit LAN: Realtek ALC888VC Graphics: Intel GMA 4100
So all depends which OS you are using, I did have Windows Vista and 7 installed on a DQ965GF, when i have transferred all the system on to a new board DQ45CB, it worked fine for me, compared to Windows XP, i got a nice BSOD.
Possibly, before installing the system to the new BOARD, uninstalling all the installed drivers from the Device Manager to avoid conflicts.
All the best,