FS2004 forward view freeze

I'm having a problem with the forward view in FS2004. I'm running FS on a Tripleheadtogo with 3 LCD screens for the front view and 2 other LCDs for the side views. It was working fine until recently. Every minute or so the front view will freeze even though the aircraft is still moving on the side views. I have to double-click the title bar to restore (screen is moving again) and then maximize again. A minute or so later it does the same thing. Pretty hard to make a decent landing under these circumstances. I recently upgraded to Windows 7. Not sure if thats when the problem started.JerryCOCKPIT SYSTEM SPECSHome Cockpit based on B747-400Dlink RouterLinksys 5 Port SwitchAltec Lansing VS5237 5.1 Surround SoundSYSTEM 1(COCKPIT-1)NForce 780i LT SLI MotherboardCore 2 QUAD Q9550 @ 2.85 GhzOCX 4GB 800MHz DDR2Evga GTX 285 DDR3Evga 8800 GT 512MB DDR3Seagate 500GB SATA IISeagate 1.5TB SATA IISoundBlaster Audigy2Cooler Master 1200w PSMatrox TripleHeadToGo(3) Samsung 46