Graphics Card working but no signal on monitor

[sakisasa24]

Hy, i have a problem with my motherboards pci-e, when i insert a Graphics Card nothing shows up on monitor, but when i insert it on intergrated graphics everything works fine. I checked Bios and it was on pcie/igfx/pci... I dont know what to, any help? The Cards that i was using were Nvidia GT 220 and Nvidia Gtx 9800 with 6pin...

 

[geofelt]

Dumb questions...
Did you attach the monitor to the discrete graphics card and not to the motherboard?
Does the monitor have an input selection switch that you must set?