# MOTHERBOARD ATX 12V PROBLEM



## gitabai (Nov 15, 2012)

My CPU(MOTHERBOARD) shutdowns automatically when I'm switching on the CPU... my friends says it resets the power.... when the ATX 12v connector(which is came from SMPS FAN) is not connected with the mother board it did not power off if i connect means the problem begins ... help me....
Here i attached some model photos....


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## Tyree (May 10, 2009)

If the PC powers on when the 4-pin CPU power connector is "not" plugged in, that indicates a PSU problem.
PC Specs?
Pre- Built Brand & Model Number
Custom Built- Brand & Model of Mobo-CPU-RAM-Graphics-PSU.


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## gitabai (Nov 15, 2012)

thanks tyree for your reply...

i tried another my friend's PSU(SMPS) in my machine same problem occur

CPU: AMD athlon 64 
OS: windows XP
RAM: 1GB 
MOTHERBOARD:GIGABYTE 
MOTHERBOARD MODEL NO: GA-K8VM800M
PSU: MERCURY 
PSU MODEL NO: MEF8450 
450W


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## Wrench97 (May 10, 2008)

The 4 pin ATX connector is the CPU Power Connector, if you are saying the fans start and run when it's not plugged in? Then that is normal as the CPU has no power to control them.

Is the heat sink tight to the CPU?
Have you tried clearing the CMOS using the jumper on the motherboard?


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## gitabai (Nov 15, 2012)

thanks Wrench97...
ya tried that but it not useful ....


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## gitabai (Nov 15, 2012)

any other chance to reset the bios....


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## dannpp2012 (Aug 5, 2012)

Yeah there is, unplug the power from the back of the tower and then remove the cmos battery for 5 to 10 minutes and then reinsert it. After you put the battery back in and plug the power cord back in turn on the pc, all bios setting will be wipped out so you will need to redo the settings.


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## Wrench97 (May 10, 2008)

Removing the battery and using the jumper do the same thing, reset the bios to defaults and clear any detected hardware settings.

Have a look at the capacitors for any signs of domed tops leakage or missing cans.
> Badcaps.net - How To Identify




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