Scenery/Graphics Problem in FS2002

My sim setup consists of 3 networked PC's with VIA chipset mainboards and AMD Athlon processors. The "flying" PC uses a GeForce 3 TI4200 64MB videocard, the "spot plane/FSNav" PC a GEForce 3 32MB videocard and the "outside view" PC a Matrox Parhelia 256MB Triple Head videocard running 3 monitors.The video drivers are both Detonator 41.09 for the GeForce cards and the Matrox driver for the Matrox card. The setup has not given me any problem since the video drivers were installed about 2 months ago and I have been happily simming every weekend.Over the last 2 weekends, I have problems with the 2 PC's with the GeForce cards. Even when starting up with the default Meigs/C172 situation, the aircraft hangs about 1,000 feet AGL and the textures creep as the aircraft moves. Frame rates remain in the 30's though. Slewing the aircraft downwards does not work though it can be slewed upwards.When in networked mode, the PC with the Matrox card works fine with the aircraft firmly on the ground and behaving normally when flown but the PC's with the GeForce cards still have the aircraft hanging in the air and the textures still creep as the aircraft moves.I have tried reverting to the previous Detonator driver version but the problem persists. Is there any solution other than re-installing FS2002?