This may have been what fixed the problem for me.
Open up the NeverWinter Nights Diamond Edition Folder
Find nwnplayer.ini
drag it and move it to your desktop
open it and find "Client CPU Affinity=" and change whatever number there is to -2
save it, then drag it and drop it back into the neverwinter nights diamond edition folder
try to reboot the game as administrator ....
CPU affinity doesn't make any difference unless you are on a P4 and you somehow stuck it on a virtual core (not a real core, but a hyper-threading one).
Also CPU affinity of -2 does exactly the same thing as 0, the default value as -2 is simply a nonsense value.
If you have had a change after this, it is merely coincidence.
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Drivers, DirectX, 1.69 patch, and Windows XP SP3 compatibility mode is what you need.
1.69 Patch:
http://files.bioware.com/neverwinter...HotUUpdate.exe
DirectX issues:
On newer installs of Windows, you may be missing some older DirectX files:
can directx 9 co-exist with directx 11 on windows 7? - Microsoft Answers
Have DirectX 11 won't play games, says I need DirectX 9.0c - Microsoft Answers
Drivers:
That and directly install latest graphics card drivers from NVidia/AMD, I have had odd results installing graphics driver updates from "Windows Update".
Compatability mode:
Properties-> Compatibility tab
check -> "Run this program in compatibility mode for:"
select -> Windows XP (Service Pack 3)
under Privilege Level,
check-> "Run this program as an administrator"
I have run NWN on my Win_7-64 machine through all of the original campaign (+SoU and HotU) and several third party modules, sometimes playing 6 hours straight. It is rock solid. This is my favorite game of all time. I was playing HotU again on Sunday past.
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