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Must Unplug/Plug-in PC before it can Pwr Up

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cisscott

IS-IT--Management
Apr 21, 2003
115
US
I have 3 older model Desktop PC towers (p2 300 - 400) that are giving me a strange problem. The PC will not power up unless you unplug it from the wall, plug it back in, and then press the power button. I have replaced the power supply in one of these, and it did not solve the problem. I don't really want to buy more power supplies if thats not whats causing it. Any suggestions?
 
i had something simular some years ago. Was a PII 233MHz with the same problem (no brand). It had a soft power button, wich was actually controlled by the bios. An Bois upgrade solved the problem.

Chekc how the power button is connected internaly, directly to the powe supply or like in my case, via the motherboard.
good luck
Robert


Robert Wullems
Network Specialist
SCP/SCE/SCM/CNX/MCP/MCSA/Network+
***************************************
If you can Sniff it, you can solve it!
***************************************
 
Thanks Robert. Ill flash the BIOS and see what happens. All 3 of these machines have power switches leading to MB Headers. Scott F.
 
Check on system board for bad capacitors.

Rich

I shall use google before asking stupid questions!
 
that is easier said then done. You can only see if a (eletronic) capaciter is bad, if it is actually blown up (You will smell this too, i can tell you). A lot of times, they are internally damaged, then it is visual not possible to detect.........
regards,
Robert

Robert Wullems
Network Specialist
SCP/SCE/SCM/CNX/MCP/MCSA/Network+
***************************************
If you can Sniff it, you can solve it!
***************************************
 
Stuff gets old you know. Everything wears out eventually. There comes a time when you have to decide whether it is so old that fixing it will cost more than it is worth. I know a new computer purchase is costly, but sometimes it is worth considering. If it is not the power supply it is probably the motherboard or the switch. One solution is to just not turn it off.

I think your computers are giving you a warning signal that they are about to give up.

If you do not like my post feel free to point out your opinion or my errors.
 
ceh4702, you are exactly right. It's a battle I have been fighting since I became the IT Mgr here. I have done fairly well at it, seeing as I have purchased a new 2 node cluster in place of our crappy little Small Biz Srvr 2000, and 21 new IBM PCs to replace old model ones. However, there are still a lot hanging on that I can't squeeze into my budget for another year or so. It's alright though, it will help keep my hardware troubleshooting skills from withering away. I had read about this problem on technet, and people were saying that a peripheral or drive could be the cause of it, if when you tried to power up, it draws too much of the power away from the start up process and the MB wont fire up. I tried disconnecting drives, but didn't see any change. And guys... If its bad caps on the MB I'm scrooged anyway, since you can't replace these ancient things. Thanks for all the input !
 
When you replaced the P/S in one of them, did you replace the power cable as well?

Jeff C.
A+, Net+, MCP, MCSA

If all else fails, read the directions.
 
Jeff - I did.. the power supplies I order come with new cables, and I love a chance to throw away an old nasty cable with 5 years of under-desk dust bunnies attached to it !
 
are that at or atx boards you are talking about?
try to slow down the bootproces by enabling the normally disabled stuff(search for floppy, extended memory check....)
have you set any powersaving options in bios?
 
What happens if you put a power strip in between the pc and the wall. Try a normal shutdown routine, shut the power strip power button off....wait...reverse order -anything?
Also - definitely look into the BIOS settings for Fast Boot, Quick Boot, PME settings (similar to ACPI soft on/off)....
What's the Power Button settings in BIOS?....the ATX defaults to hold for 4 seconds = off.

TT4U

Notification:
These are just my thoughts....and should be carefully measured against other opinions.
Backup All Important Data/Docs
 
BTW cheap things to replace are the CMOS batteries - they may not be holding the PME settings cause their Dead/Dying....they're 3-4 yrs life expectancy...and cheap to replace.
Did all 3 start this behavior at once?
All 3 connected to same Power Mains/Circuit in wall outlets.?

TT4U

Notification:
These are just my thoughts....and should be carefully measured against other opinions.
Backup All Important Data/Docs
 
Probably would suggest a meter to verify that the power on signal is not making it through the motherboard. Most M/Bs have some power up circuitry, through several TTL gates that actually pull the PS up and hold it up until shutdown.

If the switches are good, and the signal doesn't get thru, you are looking at replacing the M/B. Not a bad job, and not that expensive, but depending on the OS can get to be tedious.

Ed Fair
Give the wrong symptoms, get the wrong solutions.
 
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