Bad Power Supply? PC doesn't boot

My PC is fubar.  When I turn it on I can hear the drive spin up and the PS fan come on.  The normal boot sequence takes about 90 seconds.  The drive clicks for about 10 seconds and then the boot stops.  The monitor does not show anything.  I assume that it is not a HDD problem or I would get the FDD error from the bios, and it can't be a monitor probelm or esle it would complete the boot sequence.  All I can think of is that there is a problem with the motherboard or with the power to the board.  I don't know how to test the PS and see if it is working properly.  The fan and peripherals are powered up but since the motherboard has quite a few more connections I assume that whatever part of the PS supplies the board may be faulted while the rest of it may be operating.  Please tell me how to test the PS output to the Mother Board.  I have a voltmeter but don't know what leads to check and wether to check them to ground (the frame) or to another lead.  
ltusnrAsked:
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rmarottaConnect With a Mentor Commented:
Glad you got it going, Jay.
Regards,
Ralph

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rmarottaCommented:
itusnr,
Here's a link for the poer plug pinouts:

http://name1.cyberzone.net/~donath/pcpspins.htm 

Let me know if you need more.
Regards,
Ralph

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ltusnrAuthor Commented:
Ralph, the link you gave me is a good place to start, but I was hoping for a more detailed troubleshooting proceedure.  

Thanks, Jay
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rmarottaCommented:
Try this:
Remove all adapter cards from the motherboard except video and minimum RAM.
Unplug drive data cables and power supply connectors. (HDD, FDD, CDROM, printer, etc.)
Start computer with monitor & keyboard connected.
Anything on screen?
Keyboard LEDs flash?
Ralph


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harley47Commented:
What kind of Motherboard is it?  What size power supply (250w 300w)?  
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swwelshCommented:
I'm not sure this is your problem, but here's how to test your power supply. Set your multimeter to DCvolts at the next setting above 12v. Plug in the power cord and turn on the power supply switch. CAREFULLY insert the black multimeter probe into the P8 plug on one of the black wires. Put the red multimeter probe into one of the red wires on the P8. You should get +5V. Next put the red probe into the yellow wire. This should give +12v. Next the blue one, should get -12v. On P9 plug, do the same - black probe to black wire. Red probe to the white wire, should get -5v. Do the red wires on P9, they should read  +5v. If you have the newer type power connectors, it should be similar but I haven't tested one so I am not sure. Values within 10 percent or so are ok. In any event, I would be skeptical that this is your problem. In my experience, power supplies go bad rather suddenly. Try the things Ralph said, he didn't get a billion points for nothing.
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SirCalebCommented:
rmarotta's suggestion is where I would start....it's the only way you can successfully trouble-shoot your system.
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strowgerCommented:
You can check to see if it is a HDD or FDD problem by disconnecting them(power and data), you'll at least get the memory count, post errors etc.. on your screen.
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ltusnrAuthor Commented:
Ok guys, thanks for the answers.  Now for another poser.  In order to see the other answers I had to grade Ralph's original answer.  Now that I have seen all of them I'd like to award some points but I can't seem to figure out how.  Seems like once I graded the original answer the question has been "answered" and the points awarded.  Any suggestions?

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theh95Commented:
Do you have voltage meter, if you do you can test the power supply. set your voltage meter to DC and the turn on your power supply.  the black wires always ground (-).  you put your (+) lead to the red or yellow wires.  Then you should get the 5 volt and 12 volt read out from your meter.  5 Volt are for most Digital signals and power up the chips, and 12 volt are for the step motors for your drives.  If you got the read out from the meter, you have no problem for your power supply.  If you don't have the meter to test, you can get one from Radio Shack. They cost around $7.00 to $100.00.  The $7.00 one could work for the PC.

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rmarottaCommented:
>  "In order to see the other answers I had to grade Ralph's original answer."

You haven't graded my answer yet, you rejected it!
You have no grading options right now because I'm submitting a comment.... not a proposed answer.

I'll post another answer when you want me to.... IF I have solved your problem.
 
Any time the answer that has been proposed has not solved the problem to your satisfaction, simply select "Reopen the question to another expert" from your list of options. (You've already done that)  You do not have to accept an answer until your problem is solved.

All you need to do is select a letter to grade an answer when you're satisfied with it.  That will award the points to the expert whose proposed answer is currently pending.

Now, where do you stand, regarding the dead computer problem?

Ralph

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donagustinCommented:
If your computer actually powers up the peripherals, then the board itself is getting power that it needs.  What it sounds like to me, is that your video card is not working.  Try and drop in another video card, and see if the issue goes away.

Don
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rmarottaCommented:
ltusnr,
You now have an answer proposed by donagustin.  If it doesn't solve your problem, just reopen the question.
You can reopen the question as many times as it takes, until you are satisfied with an answer, and want to grade it.
Ralph

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ltusnrAuthor Commented:
Donagustin, Tried it didn't work.  Ralph, I took your suggestions and stripped out all the components including the drives.  I connected just the keyboard and monitor card.  I get the leds on the keyboard to flash but still nothing further.  Checked all the chips to make sure they were seated properly and checked all the connections.  Everything seems to be fine. And thanks for the info on Q&A
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OttaCommented:
> I stripped out all the components including the drives.
> I connected just the keyboard and monitor card.
> I get the LEDs on the keyboard to flash but still nothing further.

What more *COULD* happen?
You removed the drives,
so it couldn't even *TRY* to boot.
Re-add a floppy-drive, and try again.
If successful, re-add the hard-drive, and try again.
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strowgerCommented:
No, you would at least get the memory count and controller errors on your screen with no FDD or HDD hooked up.. no need to be *SARCASTIC* and put everything in *CAPS* with *ASTERISKS* around it.. give the guy a break he's asking for your help...
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OttaCommented:
How does the following help the guy solve his problem?

> no need to be *SARCASTIC* and put everything in *CAPS*
> with *ASTERISKS* around it.. give the guy a break

> he's asking for your help...

To quote the great Homer:  DOUGH!
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strowgerCommented:
I refuse to enter a battle of wits with an unarmed person.. now back to the subject at hand..  

I would say that you more than likely have a bad video card (as donagustin mentioned above) or your supply is gone... most good computer shops have the equipment to test your supply and might have a video card or two laying around to test your machine... the other possibility is that something on your board has gone( bios mebbe)....
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ltusnrAuthor Commented:
I tried swapping the video card no dice.  I am not getting the memory count or any beeps from the bios.  Tonight I will try the monitor and take a voltmeter to the power supply.  I'll write back what I find.  I appreciate all of your advice but my problem isn't solved yet
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ltusnrAuthor Commented:
Saw something nosty about a CIH virus today that wipes out a flash programable BIOS.....Supposed to trigger ont he 26th....same day my computer failed...hoping and praying that it's just an ugly coincidence.
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johnsonmCommented:
It does sound as though your bios is faulty, I think it is the virus.
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ltusnrAuthor Commented:
OK....irritating as it may be, last night I took the whole thing apart down to the jumper settings on the Main Board and reassebled it piece by piece, testing as I went, and guess what?  The Darn thing is working fine.  WTF???  Anyway, thanks to all of you who assisted in this question.  Ralph, since your second comment was the proceedure I used please post another answer so I can award points.  Thanks again to all of you.  Jay
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ltusnrAuthor Commented:
Thanks Ralph, now if I only knew what it was that I did to fix it......

Jay
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rmarottaCommented:
Jay, here's one possibility:
I have seen bent pins in the monitor cord's plug cause the same type of problem.
Simple re-connection inserted the pins far enough into the video card connector to make contact.
Look closely.
Ralph

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