Having been through multiple installations, different BIOS versions, nvidia driver versions, and having crossed my fingers a few too many times, I've finally had a breakthrough on the issue of getting past AVWizard.
Problem I was having was as follows: AVWizard gives blank screen regardless of selected output connection (1,Q,2,M,3,4,5) and resolution (6,7,8,9,0)
I went through AVWizard blind and took a look at Xorg.0.log. It was reporting "no requested modes" and reverting to "nvidia-auto-detect" 1024x768, and my display was having none of it. Even though AVWizard set the correct "1920x1080" modeline in the monitor section of xorg.conf, X server wasn't trying to use it apparently. Issue was solved by adding the following to the Screen Section:
Subsection "Device"
Modes "1920x1080"
EndSubSection