From: Mike N. 

http://weblog.infoworld.com/enterprisedesktop/archives/2007/05/vista_reboot_ma.
html

"It's madness, I tell ya! Shear madness!

Recently, I installed one of the myriad nVidia display drivers for Windows
Vista (rev. 158.24 to be exact) and within 24 hours the operating systems
was forcibly "downgrading" my XPS M1710 notebook to an older,
WDM-certified version. Worse still, it did this without my consent,
courtesy of the new, more aggressive Windows Update.

The final straw came today when, in an apparent fit of over-protectiveness,
Vista decided to perform the downgrade - 4th time in as many days - while I
was in the middle of constructing a complex web query. Suddenly, all of my
applications started shutting down. I then saw the familiar
"Installing Updates" message as Vista completed the
"downgrade" and rebooted the machine.

Bottom Line: It's the middle of the workday and my PC is rebooting on its
own, without so much as a warning dialog, all because Vista can't recognize
the installed video driver. This is nuts! ...
"

--- BBBS/NT v4.01 Flag-5