Someone else with this same issue (here) fixed it by running the game in compatibility mode (see below for the other suggestions). While in the compatibility tab you could also try disabling desktop composition (that helped a couple people with graphics issues in Vista/7 with Divinity 2).

Originally Posted by Larian_QA
Reinstalling directx 9.0c might help with this issue.
http://www.microsoft.com/en-us/down...m_en_us_search_mssuggests_131z4enus22051

If this does nto fix it, please try setting your resolution to 16-bit and let us know if that fixes the issue.
Right click on desktop > screen resolution > advanced settings > list all modes > select 1680x1050 16-bit (60Hz)

You could also try right clicking on the executable and setting compatibility mode.
Go to C:\Program Files (x86)\Steam\steamapps\common\divine_divinity > right click on div.exe and click properties > compatibility tab > check the box next to "run this program in compatibility mode" and try windows xp sp3.

If you still have the problem, please contact support@larian.com.