How do I play the original Dungeon Siege on Windows 7?
Run the DSVideoConfig.exe in the installation directory, and explicitly select your video card (rather than the default "Primary Display Driver - Hardware" or "TnL").
Also, it looks like an additional step is needed for Legend of Aranna to work. Copy the first line from the DungeonSiege.ini file in the Dungeon Siege folder to the DungeonSiege.ini file in the LoA folder.
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