Helping a friend debug his video issue on an older computer w/ AGP 8x video card. So here's the situation:

Problem: Screen goes black a few minutes after booting to Windows (every time, not intermittent)
Disclaimer: Using latest video drivers, Windows Updates, etc...

Step #1:
1) Remove AGP video card, to try in different computer
2) Screen does NOT go black on different computer
3) Conclusion - AGP Video card must be working fine

Step #2:
1) Try a working PCI video card in the problem computer
2) Screen goes black again on problem computer
3) Conclusion - Something else is wrong (MOBO or PSU)

Step #3:
1) Return AGP card to problem computer
2) Switch out power supply with an old junky used one
3) Screen does NOT go black on problem computer
4) Conclusion - It works! So, we probably just needed a new PSU, right?

Step #4:
1) Buy brand new power supply
2) Install it
3) Screen goes black again on problem computer
4) Conclusion - WTF? It worked with an old junky PSU, so why is it giving me the same problems on a brand new PSU? (we bought PSU with similar specs)

Step #5:
1) Expose myself to TWW ridicule and google searching
2) Tell him to let it go and just buy a new computer

3/10/2009 11:10:54 AM

the monitor is bad and you got lucky in step 3

3/10/2009 11:19:06 AM

Re-verify that the screen stays on with that other PSU that you used for troubleshooting. Did that one have a higher wattage and/or was it used on a different power circuit?

3/10/2009 11:20:52 AM

^^ Yes, monitor that was used was a working one (mine, not his). If I got lucky, and it does go black, then where would the problem lie? I'm assuming MOBO?

^I'll have to re-verify. Same wattage on PSU, but what do you mean by "power circuit"?

[Edited on March 10, 2009 at 11:29 AM. Reason : hmmmm]

3/10/2009 11:28:55 AM

You have the right trouble-shooting instincts, just don't forget to double-check every step as you rule things out. I would start with the monitor next.

3/10/2009 11:29:57 AM

by power circuit i assume he means plugged into the wall in a different location?

Quote :

"If I got lucky, and it does go black, then where would the problem lie?"

errrr i was saying that you got lucky that it didn't go black

3/10/2009 11:30:57 AM

Quote :

"by power circuit i assume he means plugged into the wall in a different location?"

correct

noisy power can do some strange shit to computers

3/10/2009 1:18:57 PM