Strange Power Problem

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Pooky

Garfield's Teddy
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My computer has done this several times before and now has just done it again.

What happens is if it is unplugged from the power for an amount of time, it won't switch on after plugging it back in. What usually happens is that I leave it plugged in for a while and then it suddenly springs to life.

Today it isn't doing that.... It leads me to believe that my problem is the CMOS battery? I'm not sure if it is flat but I have replaced it before and it didn't seem to make a difference.
 
To me sounds like PSU but i could be wrong do you have a very big PSU ?? may be the caps charging.
How long does it take before it switches on is it about the same length of time all the time or does it vary ??
 
Perhaps try to short those 2 wires on the psu to make sure the psu is working? I can't remember which 2 it is, I think it's the green one in the middle and the one next to it - check on google just to make sure. If the psu is fine the fan will power up.
 
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FNfal said:
To me sounds like PSU but i could be wrong do you have a very big PSU ?? may be the caps charging.
How long does it take before it switches on is it about the same length of time all the time or does it vary ??
Click to expand...

It varies every time. Sometimes it turns on after 2min, sometimes 10min, now it's been over 30mins still hasn't come on.
 
FNfal said:
To me sounds like PSU but i could be wrong do you have a very big PSU ?? may be the caps charging.
How long does it take before it switches on is it about the same length of time all the time or does it vary ??
Click to expand...

It varies every time. Sometimes it turns on after 2min, sometimes 10min, now it's been over 30mins still hasn't come on.
 
Pooky said:
It varies every time. Sometimes it turns on after 2min, sometimes 10min, now it's been over 30mins still hasn't come on.
Click to expand...
Sorry bro defiantly sounds like PSU but i could be wrong
 
You PSU is dying!

This is a common symptom of a PSU on it's way out. Next step might be it switches "on", fans spins, lights are on but you get no POST beep or it might just die outright.
 
It's a 500W PSU - I see PC Zone is selling a 450W Thermaltake PSU for R299

Will that be okay? I'm running quite old hardware:

Gigabyte 965 MOBO
Core2Duo 1.8Ghz
GeForce 9600
 
Pooky said:
It's a 500W PSU - I see PC Zone is selling a 450W Thermaltake PSU for R299

Will that be okay? I'm running quite old hardware:

Gigabyte 965 MOBO
Core2Duo 1.8Ghz
GeForce 9600
Click to expand...

It's not the best out there (Stick to Antec, Corsair, Seasonic for decent stuff) but it will do the job ;)

I purchased one of the 350W ones on Friday for someone else but they did not have a discreet GPU. So stick with the 450W. I had a 460W running on my pc (specs below in sig) and it was fine.

Don't you have another PSU to test with first?
 
ponder said:
It's not the best out there (Stick to Antec, Corsair, Seasonic for decent stuff) but it will do the job ;)

I purchased one of the 350W ones on Friday for someone else but they did not have a discreet GPU. So stick with the 450W. I had a 460W running on my pc (specs below in sig) and it was fine.

Don't you have another PSU to test with first?
Click to expand...

Yeah I will test it with my brothers' PSU now...

Howcome it worked perfectly when constantly connected to power but as soon as it is unplugged from power for a bit it stops working?
 
Okay tested with another PSU and still won't switch on... Any other suggestions?
 
Pooky said:
Okay tested with another PSU and still won't switch on... Any other suggestions?
Click to expand...

Have you tested another appliance in that wall socket? :D

Otherwise I suppose dead mobo?

Check the actual on switch for the pc case as well, I once had a pc that I thought was dead but the actual switch that you press to turn on the pc was just not working.

You can also try taking out anything from the pc that's not neccessary for it to switch on eg. hard drives, gpu, sound cards etc. to see if it isn't one of those.
 
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stevovo said:
Have you tested another appliance in that wall socket? :D

Otherwise I suppose dead mobo?

Check the actual on switch for the pc case as well, I once had a pc that I thought was dead but the actual switch that you press to turn on the pc was just not working.

You can also try taking out anything from the pc that's not neccessary for it to switch on eg. hard drives, gpu, sound cards etc. to see if it isn't one of those.
Click to expand...

Yeah the wall socket is fine :D

What I don't understand is that this problem has happened before and every time it has come on after a while, which leads me to believe it's something to do with the PC not being connected to the power all the time - surely if it was another component causing it, the symptom wouldn't be that the computer is unresponsive after not being connected to power?
 
Pooky said:
Yeah the wall socket is fine :D

What I don't understand is that this problem has happened before and every time it has come on after a while, which leads me to believe it's something to do with the PC not being connected to the power all the time - surely if it was another component causing it, the symptom wouldn't be that the computer is unresponsive after not being connected to power?
Click to expand...

In that case my bet would be the motherboard - but that's just my logic, hopefully someone with more experience with something like this can confirm

Have you tried checking the motherboard for any leaked or bulgy capasitors?
 
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Its an old computer - and likely overloaded with dust.

Remove the power connector on the motherboard from the PSU, ensure its 'clean' and then reinsert. Ensure that the connector clips in correctly (it should make a distinct sound).

Do you notice that your system clock (or time in windows) is sometimes inaccurate after these incidents? If so, it could suggest a dead bios battery.
 
stevovo said:
In that case my bet would be the motherboard - but that's just my logic, hopefully someone with more experience with something like this can confirm

Have you tried checking the motherboard for any leaked or bulgy capasitors?
Click to expand...

I will check this now.

yeti said:
Its an old computer - and likely overloaded with dust.

Remove the power connector on the motherboard from the PSU, ensure its 'clean' and then reinsert. Ensure that the connector clips in correctly (it should make a distinct sound).

Do you notice that your system clock (or time in windows) is sometimes inaccurate after these incidents? If so, it could suggest a dead bios battery.
Click to expand...

I changed the CMOS battery just to be sure. I will check the dust now.
 
Okay no bulging anything. Connectors removed and replaced and checked... Still nothing...
 
Pooky said:
Okay no bulging anything. Connectors removed and replaced and checked... Still nothing...
Click to expand...

So the times that the computer did actually switch on, it ran perfectly fine? even if switched off and then on? So only after removing it from the power completely does it give you these problems?
 
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