PC requirements for 3x Projector on 1PC

hello,

Did somebody try to make 3x Projection system using 1 powerfull PC ? I want run under FSX on Vista 64bit

I need 3x 1920x1080 resolution wich gives me three BenQ W1000..

I wanted to use TH2Go but then noticed that his maximum resolution is 3x 1650x1080

I want to use :
Processor:INTEL Core i5-860s Quad-Core
Motherboard:ASUS P7P55 WS SuperComputer
Graphic Card:GIGABYTE N285UD-1GH
Memory:2x Kingston 4GB Kit DDR3 1600MHz CL9 HyperX
HDD:WESTERN-DIGITAL Caviar Green 2000GB 64MB
DVD:LG GH22NS
Watter Cooling System: Thermaltake ProWater 850i
Case:Thermaltake Mambo VC2000BNS, 850W

My question is how to get 3x 1920x1200 resolution on my curved screen ? (Do I have to add one more Same graphic card and connect projectors to 2x DVI and 1xVGA seperatly or to use 1 graphic card and connect 2 projectors TH2Go( can give 2x1920x1200) to DVI output and 3rd projector to VGA output on the same graphic card ?

Can even GIGABYTE N285UD-1GH mannage 3 projectors at so high resolution ?

Thanks a lot!