Text isn't as clear in portrait mode
So I saw a picture of Bill Gates computer, a 30" Dell with 2 widescreen monitors in portrait on each side, and I tried to do this myself. I already have 2 x 22" so I got a 30" Dell. Problem is, when I turn the 22" in portrait mode and turn the monitor on its side using the Nvidia control panel, the text isn't quite as crisp, you really have to look up close its not obvious but its there. I tried on another system using an 8800GS and same story. Thing is, I can't find a single thing on this phenomena anywhere on the web so I'm hoping someone can let me know whats going on here.
The problem is you're using TN panels. Banding issues and low viewing angles aren't too bad in landscape but the second you move them into portrait you basically get ass-on-a-stick.
If you want to resolve this upgrade to pva or ips. Both offer vast improvements in portrait. Of course there is the small issue of price.
TN panels have poor viewing angles. The results you are seeing are likely due to color shifts that generally affect TN panel monitors. It is a limitation of the technology itself.
There is nothing you can do about other than:
1. Live with them.
2. Replace them with more expensive monitors that uses *VA or IPS panels.