Original install of W7 did not support dual monitors. Symptom was primary display blue and right display black with no way out. Went back to single monitor and installed the same driver I got to work in Vista and it worked great - 158.24_forceware_winvista_32bit_english
Problem solved
Motherboard Asus P5WD2E, EVGA eGeForce 7900GT KO, Pentium Extreme (Presler) @ 3.47G, no overclocking, Seagate ST3160812AS, no RAID, PC5300 2G memory. Nothing special by today's standards. So far so good :)
Tried the latest nVidia driver for W 7, 185.85_desktop_winvista_32bit_english_whql, no joy. Symptoms are primary display looses sync and secondary display is fine. If you unplug the secondary the primary will remain out of sync and you must restart. The instant you plug in the secondary the primary looses sync again. Uninstalled the 185.85 software then reinstalled the 158.21 all worked great. Not sure why nVidia has fixed this yet, but, without this old driver multiple displays do not work on my system. Device manager indicates the working driver version is 7.15.11.5824.
Quote