My 27 inch Apple Cinema Display has a blue tint to it when connected to my laptop, which uses Optimus (NVIDIA + Intel). I believe the Intel actually handles the output signal in all cases, and the NVIDIA only does the processing.
When connected to my other laptop or my desktop - both having ATI cards, the video looks excellent with normal reds / greens / blues.
DisplayPort is the connection in question.
I've tried tweaking the settings through software (Windows, graphics drivers in NVIDIA and Intel), all to no avail.
The white balance seems horribly tinted blue. I'm VERY close to turning my laptop in and getting a different one because of this issue.