FSX VC night textures

Hi,I have spent a lot of time reading many posts about the VC night textures in FSX.Just recently I have installed FSX on my new W7 computer with wide screen monitor (2048x1152) and nVideo GTX240. My first flights were during daytime so I had not noticed it, but than yesterday I wanted to fly at night. So far I have only been flying the default 738 just to see if I should abandon my fully loaded FS9 and switch to FSX completely. When I loaded the 738 the VC was missing. It was there when I switched to daytime, but gone at night. So were the plane textures. I could only see the wings, ailerons and wheels. I had just installed the SDK as well and feared that was the culprit, but now I am not so sure.I read about sound cards being downgraded and other video card issues and I read about switching to preview dx10.I dont know why, but that works for me. I have the VC panel back at night and all seems to work well.Since I am also using this pc for my work, I do not wish to start massing with dll