Thank you for that point-out, Zander. This one is definitely bad on me. I have violated several guidelines listed at the bottom of the first post there. First, I never removed/purged the nvidia-glx-new package or the linux-restricted-modules. Since I originally installed the 9755 driver that way, it makes sense that only it will work now.
I greatly appreciate your time. Looks like I have some work to do to resolve this on my end.
BTW, I bought the 8800GTS card for my new PC build two weeks ago because of NVIDIA's great support to Linux users. Thank you for continuing to support the Linux community. I realize that there are some FOSS purists who hound your company and others, but the bulk of the Linux community I see on the various forums greatly appreciate your support and understand/honor your intellectual property rights. Please keep up your great work and pass this post on to your fellows and leadership there at NVIDIA. The 8800GTS is an awesome achievement, and it runs great under Linux!