I have run into a bug with my new Dell at work that it won't load the Intel on-board video drivers. It says something like the drivers won't work in VGA mode when I try and get it going for three monitors. But the nVidia 5200 256MB PCI card works fine
and AERO works with it great.
That stinks you can't get either of your cards working. If you are a technical tester I would imagine they will get a new build in the next few weeks, so hopefully the updates fix your issues.