Monitor goes into standby after login. this happened after install

[Guest]

Installed sp2 on 15 hp desktops. 3 machines now boot to the login prompt, as
soon as you enter userid and password ,the screen blanks and the monitor goes
into standby. the power light on the desktop is on ,and the led on the
monitor is orange (standby), will not wake up from ketboard or mouse. power
of and the cycle starts again. contacted HP there advise was contact
Microsoft. correct drivers installed

 

[Malke]

Installed sp2 on 15 hp desktops. 3 machines now boot to the login
prompt, as soon as you enter userid and password ,the screen blanks
and the monitor goes into standby. the power light on the desktop is
on ,and the led on the monitor is orange (standby), will not wake up
from ketboard or mouse. power of and the cycle starts again. contacted
HP there advise was contact Microsoft. correct drivers installed

Before you installed SP2 on the 15 HP workstations, did you also apply
the various HP patches that needed to be installed *before* installing
SP2? IIRC one of them was for the video.

In any case, uninstall the video card and then either allow Windows to
find it OR install the latest drivers from either HP's site for those
particular machines OR from Nvidia or ATI. Since you didn't tell us
what video hardware is in those machines I can't guess. You might try
rolling back to the drivers that worked, too. I think I'd try that last
thing first.

How to Roll Back a Device Driver - http://tinyurl.com/86yb6

Malke