Desktop PC won't power up

eddietash

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May 4, 2011
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18,510
Hi,

I hope someone out there can help me. I've just got back from Easter holidays and tried to turn my PC on but nothing happens.
I never have the power off from the wall socket so the mobo LED is always on.
I've tried unplugging and using a different power supply etc but no joy.

The only thing I noticed is when I switch on the power from the PSU the cooling fans and the CPU fan twitch and the mobo LED is green.
But the power button on the PC doesn't fire up the PC, it's dead......
I checked the connections and all seems okay.

Is it something to do with my PSU or Mobo??????

Anyone any ideas?

 

ghnader hsmithot

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Hi Ed,
I think with most people the green light often means your mobo has not gotten enough power to switch on your machine.It should be according to your psu,However sometimes it can also refer to ram being faulty or not being seated properly.
 

Uther39

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Yeo, make sure everything is seated properly, RAM, GPU, USB cables to your Mobo etc etc, all power cables, if this fails try to borrow another PSU to try, however i had a problem a year or 2 ago the same as this with a friends PC it turned out his CPU was dead, mind you it was an old P4, can we have your complete system details please.
 

eddietash

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May 4, 2011
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18,510
Hi,

it's quite an old system that I bulit back in 2004. I've forgotten the exact specs but here goes.....

Mobo Asus P4c800-E Deluxe
CPU Pentium P4 3.0 Gigahertz
RAM Corasir 2x512 DDR400
Graphics ATI Radeon 9600
PSU Antec 480W True Blue
HDD 2x160G SATA RAID 0
OS XP Pro

up until easter I never had an issue at all
 
Check the mobo for bulging or leaking capacitors. Google "bad capacitors" to get images and other information on this well-known issue. You say you tried a different PSU, so it probably isn't caps in there.
 

eddietash

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May 4, 2011
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18,510
Hi,

no can't see any Leaking/Bulging capacitors, everything looks fine.
No smell either of fried components.
Not yet tried a different PSU though.

Would just like to know when I switch the power on via the PSU (I/O), if the Mobo LED light is green and the Cooling fans/CPU fan twitch for a second or two, why it doesn't power up when I turn it on via the PC Button?
 
You said "I've tried unplugging and using a different power supply etc but no joy."
What did that mean, if it didn't mean you tried a different PSU? If you did not, then doing so would probably be a good idea.

The green LED does not mean your mobo isn't getting enough power; it means the PSU is providing +5VSB to it.

Rule out the power switch itself by unplugging it from the mobo and shorting the pins with something like a screwdriver.
 

ghnader hsmithot

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Sorry mate.
I had this problem before and i just found out it was my psu.However i didnt have a clue for what the green light meant i just knew it had something to do with the psu.