Motherboard gone bad?

ok so my friends computer is acting up.  When we turn on the power all the fans and drives seems to be spinning but nothing is on the screen.  You don't hear that stactic sound when the monitor is activated.  

I did a whole bunch of test.  I disconnected all the unnecessary stuff and left one cd drive and the main hard drive.  there still is nothing showing up as like there is no power to the video card, but I put a working video card into it and nothing is showing up.

Except I power off,  unplug power cord connecting to the mother board, re plug it back on.  Then I turn the comp on and the screen turns on!  what? but it usually gets frozen when u see the win logo with the animating bars.  

I even tried using a working machine power source and pluged it in.  Same problem.  I came to a conclusion that its the mother board at fault and is dying.

Everything turns on except no video display, video card works fine.  I even put the hard drive into a working machine and its starts up fine.  So right now nothing is showing up, only fans and other devices running but no video display.

any solutions?
speed_mstAsked:
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My name is MudConnect With a Mentor Systems EngineerCommented:
It could be saved... but sometimes it is more costly to fix it than to replace it, unless is a museum reliquie, every company has had one... some times are just one or two caps, other times are the FETs & MOSFETs w/o caps... but it could be save, unless the caps leak and corrosion starts eating the copper in the electrical paths... sometimes too can be fixed...



http://en.wikipedia.org/wiki/Capacitor_plague
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aimqldCommented:
have you tested the power supply?

similar problems to yours sometimes happen when a PSU is on its way out and some of the channels are under voltage.
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nobusCommented:
>>  I came to a conclusion that its the mother board at fault and is dying.   <<  solution : replace it.
before doing that, try booting without the disk and cd, and only 1 ram stick. if you get a screen, one of the disconnected is bad.
You said it starts up when you unplug/replug the power --> at this time you can test your ram, or disk : (you can use a bootable floppy or cd)
ram : use memtest86+ from :    www.memtest.org
disk : use any of these :  http://www.disk-utility.com/hard-disk-low-level-format.html
 
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YurayCommented:
it's not a HD definitely, it's very common to be a PSU, i had the similar prob, and PSU turned out to be bad, if you have a chance plug another one just to test. also check you memory modules.
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My name is MudSystems EngineerCommented:
I have seen frozen PC after boot... Do you know what a capacitor is/looks like??? check the capacitors top and see that non have blown, the slightest bump in the top of the capacitor means it is short circuited... If you have the skills and the replacement, just replace it...
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My name is MudSystems EngineerCommented:
This blown caps usually are around the processor...
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YurayCommented:
there is no chance to change capacitors yourself. if it so(i mean MoBo is dead) theonly way is to change it.
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My name is MudSystems EngineerCommented:
>>there is no chance to change capacitors yourself.

Like I said... If you have the skills and blah blah blah... I wouldn't have posted "change the cap" if it was imposible... which it is not... thank you very much, I can find my way out... :P


<just to be closing the door on the way out...>
By the way, I have done that several times, I have even change the FETS and MOS on "Dead" mobos, and guess what, they all still kicking... <:P²>
</just to be closing the door on the way out...>
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speed_mstAuthor Commented:
Power supply - nothing wrong (used another power supply to test too)

Hard drive - nothing wrong

video card - nothing wrong (used a working one to test too)

When I said unplug, replug I mean those 2 power plugs that connects directly to the mobo.  That seems to reset the power or something and video will display.

Hmm I'll have to check the capacitors.

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nobusCommented:
>>   I mean those 2 power plugs that connects directly to the mobo  <<  you mean you plugged them while the power supply was on? you may well have fried the mob by doing so (but it was probably already bad, so...)
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speed_mstAuthor Commented:
>>   I mean those 2 power plugs that connects directly to the mobo  <<  you mean you plugged them while the power supply was on? you may well have fried the mob by doing so (but it was probably already bad, so...)

Of course not!  I wouln't do it when power is still active.  I did it when power is off then power on.
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speed_mstAuthor Commented:
Ok I went to check if there are any blown capacitors.  But I dont seem to find a leaking one but I'm guessing it maybe too small of blown to dectect.  Or it may due to some sort of short circuit.
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My name is MudSystems EngineerCommented:
>>check the capacitors top and see that non have blown, the slightest bump in the top of the capacitor means it is short circuited

Sometimes this bump is quite small... but noticeable, guess the only way to know if its short circuited is by taking it out and checked with a multimeter, or if you check it in the mobo, you wouldn't know which one is damage...
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nobusCommented:
you can't tell if you've blown something by visual inspection. only tests can reveal it.
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My name is MudSystems EngineerCommented:
There has been a "Plague" of bad caps... and blah blah blah... read the wiki...
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