dual video card problems

I can't get MS Flight Sim 2004 to recognize my 2 video cards together.
System specs:
EVGA Nvidia 6600GT AGP
Visiontek ATI 9200 PCI
4 monitors
Asus K8V-X motherboard
1.5 gig ram
Athlon 3000+
XP sp2

To get both cards to run without problems in Windows I had to have only one
card in the motherboard during driver installation. But after both cards are
working well together the game only sees the AGP card. If I remove the AGP
card the game will run with the PCI card in windowed or fullscreen modes and
I can see both monitors. Same thing with the AGP card. But not both cards
together. I've tried the latest drivers from the ATI and Nvidia sites and
the EVGA and Visiontek sites. I have got this to work in the past with
earlier drivers but have lost those earlier drivers. Is there some setup
file I have to modify in fs9?

Thanks
Don