NVidea GTX670 - Triple screen possible?

If you can replace (borrow) graphics card with different one it should help you a lot with diagnose of the problem.

I know, but sadly I hate having spare parts laying around, thus don't have anything else to test with...

I don't want to tempt fate by removing my ATI6990 to try it with, but, saying that, the PC that is having the problem is my previous systemboard, and only a few months old, and had my current 6990 running on it just fine prior to upgrading my systemboard to its big-daddy...