Short description (readability and 150 char title limit):
I had a power blackout+brownout recently. The picture on screen would not show. Upon further investigation, the monitor would turn on ONLY in safe mode, until I uninstalled the driver. Drivers were reinstalled, and the monitor turns off after "Starting Windows". Otherwise, it can boot into Windows. I have uninstalled (and cleaned) all the drivers before reinstall of older ones.
Is the GPU bad?
To reiterate, the following events took place:
- power goes out for over a minute
- a few seconds after lights go out, thunder rolls
- power browns out again or goes out briefly (I was in another room, I could only see the lights dimming to zero for a brief moment)
- thunder rolls again
when I turned my computer back on, the picture didn't seem to display
- it should be noted here this was a "salvaged" Samsung Syncmaster, which entire company apparently has notoriously buggy and/or defect-ridden power supplies (Google it up, esp. LED TV), often trapping themselves in OFF mode, or eternally flashing standby lights.
- Thus the deeper problem was not immediately evident. Due to the power outage, the The monitor was refusing to turn on (this monitor has to be kept on--I have even disassembled it to look for bad capacitors, per an EEVBlog post).
Switched bad monitor for my old one. It became clear:
- blue power LED showed yellow AFTER the POST--sometimes the computer would even restart in a loop after the Windows Logo.
Further research was done (I read and skimmed a statistically large enough sample of the relevant threads on the Internet), and took the following actions:
1) Boot into Safe Mode (with networking) -- this was the only and surefire way to get in.
2) Changed resolutions to something the good monitor might scale to, since the "bad" one was 1920x1200 > 1680x1050 of the good one.
3) Restarted with various resolution settings, removing VGA, updating or changing driver to at least 2 different versions including the working one I had installed a year ago (AMD has been updating it sometimes).
4) Removed device in DM, "deleted" driver in checkbox, ran DDU, and ran AMD cleanup utility, in safe mode.
5) Restarted, monitor works. Install driver, monitor turns off.
1) NO graphics driver I installed made a difference. The computer either reset in a loop or made it to a the login screen with no video signal, but full sound and USB microphone feedback. 2) Installing the monitor driver and ICM profile in safe mode did not change anything, either. 3) The screen turns off as soon as the "Starting Windows" logo disappears, every time.
4) With no driver installed, I can boot into "regular" mode with a picture. Otherwise, the screen only works in Safe Mode.
Is my GPU toast? Or should I try uh, piggybacking another ATX supply to use the 6-pin connector?
This is on an HP-branded Tyan K8WE derivative OEM board used in an (old) workstation. The power supply is a Delta DPS-750CB that has been abused by a relative turning the circuit breaker off in anger, retaliation, etc. Both monitor and PSU were connected behind the ostensibly-functional Surge Master (1kJ prot. or so?) at the time of the lightning strike(s).