computer won't power up

Skip Cole · Post by **Skip Cole** » 22 Jun 2005 9:56 pm

In other words, push the power button on the tower to power up and nothing happens. The power supply , cord, and surge suppressor and breaker in the main box are ok. The monitor will light up ok. Shut it all down last night, this morning it wouldn't light up. What could it be? Thanks for any help.

Skip

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"I Can Only Imagine"

Jack Stoner · Post by **Jack Stoner** » 23 Jun 2005 2:28 am

Could be anything from a loose front panel power switch connector to a bad power supply or motherbord.

Some PC's have diagnostic lights on the rear that can help in troubleshooting. If yours have these check your users manual or the PC vendor's support site to see what they are telling you.

Make sure the AC power cord is plugged into the power supply on the rear of the PC. Also, if yours has a power switch on the power supply, make sure it's on or some act as a circuit breaker, turn it off wait about a minute and then turn it back on.

This all assumes you have completely checked out the power strip and know for sure there is AC power where you are plugging in the PC and that the PC's power cord is a known good cord.

Jonathan Cullifer · Post by **Jonathan Cullifer** » 23 Jun 2005 5:23 am

I don't know how clean it is, but if it hasn't been dusted-vacuumed recently, do it. I've seen many problems fixed with a spray air can and a vacuum.

Erv Niehaus · Post by **Erv Niehaus** » 23 Jun 2005 6:05 am

I just went through this. I'm sure the power unit in the computer went south.
Erv

Jack Stoner · Post by **Jack Stoner** » 23 Jun 2005 7:18 am

An added note on the hardware. Depending on the Brand of PC, if for example the power supply is bad, you may be locked into proprietary components. e.g. Dell, on their Dimension desktops, mostly use proprietary components. A stock "ATX" compatible power supply (and motherboard) will not work in most Dimension's. Same way with Compaq, IBM, HP, etc.

Dell even uses a proprietary case and the front panel power connector is not even standard ATX, so someone with a Dell Dimension (except for newer XPS series) cannot use a standard "ATX" case because of the non-ATX motherboard, power supply and the undocumented front panel connector (there is no wiring diagram or pin-out available for the Dell front panel connections).

Earnest Bovine · Post by **Earnest Bovine** » 23 Jun 2005 7:25 am

Mine has 2 power switches: a rocker in the back, and a pushbutton in the front. If the rocker switch is off the pushbutton does nothing.

Joey Ace · Post by **Joey Ace** » 23 Jun 2005 7:34 am

Good point, EB.
Sometime we overlook the easy stuff.

Along the same lines...
Some power supplies have a 220/120V slider switch in the back. If this was accidently moved to the wrong position you'd have no power. I've only seen this happen in public places, probably kids playing pranks.

Skip Cole · Post by **Skip Cole** » 23 Jun 2005 9:26 am

Here's where i am at the present :
installed a new power supply, old one had a ton of dust in it, cleaned all dust out of everywhere, plugged everything back up, made sure all power sorces were on, from the breaker box to the wall receptacle ,then to the surge protector. The big moment of truth, pushed the power button on front of the tower, it blinked one time and nothing else, still it didn't power up. Back to the drawing board, gonna open the case again and make sure the power supply has all switches, sliders, etc, on. I certainly appreciate all your help, ain't no way that i'll take this thing to a tech until i've exhausted all possibilities. Guess that's just the Irish in me.

Thanks again------Skip

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"I Can Only Imagine"

Papa Joe Pollick · Post by **Papa Joe Pollick** » 23 Jun 2005 12:54 pm

OOPS--sounds like a dead short to me..ain't a tech or guru.but the light blinkin once sounds familiar..

Michael Barone · Post by **Michael Barone** » 23 Jun 2005 4:49 pm

If you have any PCI cards installed, I would try removing them, one at a time, then try starting. Also, if you have an AGP video card, try removing it and starting, just to observe the motherboard's reaction.

Just some thoughts

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Mike Barone
Sho-Bud Pro-1, Nashville 112, Goodrich Pedal, BJS 15/16 Bar, Assorted Guitars & Keyboards

Ron Bryson · Post by **Ron Bryson** » 23 Jun 2005 6:39 pm

Check the battery on the mother board for the CMOS memory..

Wayne Carver · Post by **Wayne Carver** » 24 Jun 2005 7:29 am

When you press the switch on some PC's it goes through the motherboard to bring on the power supply. If that's the case you will have to replace the motherboard.

Jack Stoner · Post by **Jack Stoner** » 24 Jun 2005 9:58 am

Normally the CMOS battery will not cause this problem. If the battery is bad the CMOS will revert to it's default configuration, but the PC would still power on.

As someone suggested disconnect the power to the various drives, remove all PCI cards and see what happens. If it comes on, then power off, reinstall one of the cards, power back up and see if it still runs. Keep doing that with the PCI cards and the various drives until you find the one that is causing the problem. If none of the drives or expansion cards are causing the problem, and you are sure you have a good power supply, about the only thing left is the motherboard and/or CPU.

Lou[NE] · Post by **Lou[NE]** » 24 Jun 2005 3:26 pm

What about the CPU fan?

Skip Cole · Post by **Skip Cole** » 24 Jun 2005 10:03 pm

I very much appreciate all the suggestions and help you all have given. A friend of my son-in-law is a tech for a large company ; he is convinced there is a problem with the motherboard. Since the power supply has been upgraded from 180 watts to 350 watts, the motherboard, from the information you and the tech have given me, will be next. Hope the computer don't have a "fatherboard"

Thanks again to all , God bless.-----Skip

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"I Can Only Imagine"

Gary Shepherd · Post by **Gary Shepherd** » 24 Jun 2005 10:14 pm

I have some computers that, after a storm, require removing the power cable from the power supply for a few seconds before the machines will restart.

A simple way to test the power button on the front of your case it to open the case and physically short the power jumper yourself with a piece of wire or something similar.

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Gary Shepherd

Carter D-10

www.16tracks.com

Skip Cole · Post by **Skip Cole** » 27 Jun 2005 3:54 pm

I did all of the above mentioned procedures and still no juice. So i took it to a tech and he tells me it's the motherboard and he can replace it for, oh say $200. Also he said he wouldn't guarantee it to be the problem even then #$%?? Guess i'll have to save up and get another one, someday. Next time, it will be one with a fatherboard too.

Thanks again.

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"I Can Only Imagine"

John Bresler R.I.P. · Post by **John Bresler R.I.P.** » 28 Jun 2005 6:31 am

I think you took your computer to the wrong tech. I'd seek out another one because you aren't getting any kind of guarantee. After it's fixed, then you get charged. He's only guessing that it's the motherboard.

Also, with the July 4th sales at computer stores, you could probably get a new pc base for not much more.

Skip Cole · Post by **Skip Cole** » 28 Jun 2005 11:34 am

John, you're right about that. Just as soon as he got the words out of his mouth " but i won't guarentee it'll fix it ", i bid him farewell. And to think he came highly recommended.

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"I Can Only Imagine"

Jack Stoner · Post by **Jack Stoner** » 28 Jun 2005 1:08 pm

Not that the "tech" you took it to is questionable, but it may take swapping out the M/B to determine if that is the problem. Component substitution is needed many times. However, if it's a stock ATX compatible machine, he should have a M/B around that he can install, temporarily, to see if that is what the problem is and then if it is the problem he can then install or order the required M/B.

Tom Diemer · Post by **Tom Diemer** » 28 Jun 2005 4:01 pm

Any card shorting in a slot could stop power on. Also, on some bios's, having the keyboard / mouse plugged in backwords will do it too.

I assume you checked to see if the cards were seated ok. The video card sometimes lifts out of the socket on the front edge, will stop the pc from powering on too.

If you want to try "everything" before paying someone else, remove all the cards from the slots except the video card, even if it's slot mounted - many mainboards won't light up without video. Unplug the ribbon cables to the drives and unplug the power connectors from them. Unplug the mouse and keyboard, any printers and USB connections.

Still no power, it's either processor or mainboard. (processor not seated well will stop power-on too) - If you're comfortable with doing it, remove the processor fan, and lift and close the lever a few times to make sure it's seating.