Major Texture Anomoly with FS9

Hi all,My vc and aircraft textures disappear in fs9. I start a flight anywhere and about 2-3 minutes into the flight my vc and aircraft textures disappear; they turn white. I have an image to show you the problem. This usually happens when i cycle through the views. Initially the ground textures go realy blurry then the aircraft and vc textures disappear. My setup is as follows:Asus p5b deluxeApacer ddr2 800mhz memorye6600 core 2 duo 2.4 ghzmsi geforce 8800 gtx100.65 nvidia drivers (Guru3d)windows vista home premiumThis problem has happened with all drivers avail for vista to date. I think this issue was prevailent in XP as well with the same specs. Can anyone help troubleshoot this with me?? Please no remarks about vista and its bugs or "upgrade to fsx" comments (i do use fsx for use with RFP 747-200 as well and this problem doesn't occur)I need to add that this issue appeared from the default installation of FS9 as well without addons.See attachment below.Cheers,Kelvin