Asus Windows 7 laptop's external monitor has a yellow tint

Solution 1:

http://www.systemshock.org/index.php?topic=4075.0

I recently started having the same problem on my new Asus notebook. The culprit is a bloatware called Asus splendid utility. Either uninstalling or selecting normal in the option of app will fix this issue for sure.

Let me know if that helps.