I would like to set up a dual PCI-e gpu system with my new 8800gt powering my main display alongside what I was previously running, the Quadro fx1400 powering my second display.  I don't have intentions of adding more displays and I know that I can't do SLI.  I've read running 2 different cards in a dual gpu setup in non-sli IS possible.. but all have been examples of different cards in the same GeForce family and NOT a mix of GeForce and Quadros.   !!!?  I know that's due to the cards in the same family sharing drivers.. while the GeForce and Quadros do not.  Can I make this work??  Also, would there be any reason performance would be hindered in doing so?
 
....Thank you!!!

What are you trying to do with the setup?
 
Are you trying to retain Quadro features and Gaming features, or simply run dual monitors?
 
The geforce drivers will run fine with a Quadro alongside, but the Quadro drivers may hiccup with the Geforce alonside if it is used for any workstation/pro apps.
 
If the second card in either configuration is acting like a dumb second display, then you should be fine under both configurations, but expect problems if running with the Quadro drivers as your primary.
 
We've done that at work, it can be a little more glitchy than single card, but when isn't multi-monitor slightly more glitchy?
 
I don't see any major conflict since you aren't looking for either SLi or mention using it for game acceleration (which may actually be ok, but likely a little buggier than slightly buggy multi-mon support).
 
That's my two cents for a basic multi-monitor setup experience, but someone may have better experience with the same kind of setup from a gaming perspective.

Thanks GGA!  I was intending on running the GeForce as my primary with it's drivers installed and the Quadro as my secondary, hoping to utilize some of the features of both cards.
 
I have since discovered what was preventing me from getting this to work.  My system is a dual Opteron workstation and being I don't have a second processor at this time my mobo does not support a functioning second PCI-e slot unless I have that second processor.  Which explains why there was power to the card but no display output.  RAAWR!