FWIW, switching to a DVI interface instead of VGA isn't really a cure, but a "workaround" that dodges the problem by using a digital interface (DVI) to avoid using the analog interface (VGA). For people with video cards and monitors with a digital port
(DVI or HDMI) & willing to upgrade their cables and KVM's (if used, as in my case), it makes sense that it might successfully dodge the problem.
In my case the real fix was to just manually set up a custom resolution (at 60Hz rather than the 59Hz it kept switching to), and then a month or two later Windows Update offered me an updated nVidia 9800GT driver for Win 7 that also seemed to fix the problem
without needing to use any custom configuration. Since the problem I suffered only existed at 59Hz and digital interfaces don't use that parameter, it's logical one might avoid seeing the problem I saw (though not really cure it) by not using the analog interface.
I would've preferred to go digital, but the laptop connected to the monitor via my KVM only has VGA output and can't be changed. (Besides, good DVI KVM's are more expensive, and HDMI KVM's and cables are a lot more expensive).