What do you need the Quadro card for? What apps are you running.
The FX 570 will be crap for games.
My Quadro 1500 $800 gets killed in games and workstation apps like AUtoCAD, 3D Studio, Inventor ect. against my GeForce 8800GT $300.
If you have two PCI-Express slots you could run a dual boot, one for gaming, and one for workstation and run different cards on each OS boot if you HAD to.