PC Wont power Unless I leave it plugged in for Hours??

[pdb123]

I have a client whose pc wont power up unless it has been plugged in for hours.
There has been new RAM added to the machine and new Video card, I tried it with video card out, and the Ram has been in for months! Although I will not rule this out. I doubt its the CMOS battery as the pc is only about 2 years old.
When the PC works it just switches from on to off repeatedly so its on - off every 0.5 seconds.
It does the above untill the power button is pressed again.
Anyone have any ideas on this?
The PC may be plugged in for Hours before it will work.

 

[edfair]

SWAG that you have a problem power supply that is slow in getting standby power up.


Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[wahnula]

My SWAG is the same as edfairs's SWAG...an easy and cheap test would be a new PSU (always good to have a spare anyway) or a PSU tester (always good to have period). The new GFX card may have been enough to put the old PSU past the tipping point.

Tony

 

[Lienori]

Power supply, I'd bet my house on it. You'll probably find that as time goes by, it needs to be plugged in for longer periods of time before it will allow you to turn it on. Or it turns itself on after that period.

 

[G0AOZ]

And I'd even go so far as to tell you it's probably the low voltage capacitors in the output circuits of the PSU which are suffering the BAD CAPS syndrome!

Had this exact problem with an non-standard PSU and the computer was needed urgently. Changed four of the 1000uF 16vw capacitors and started up like a good 'un...

P.S. Don't try this at home unless you know what you're doing!

ROGER - G0AOZ.

 

[SkipCox]

SWAG or not, the psu would be my first stop too. A little more advice is to buy a "namebrand" power supply and stay away from any psu deal that seems too good to be true.

<rant>Caveat is that some brands always reported to be a best choice have been reported recently as a poor choice...antec is one example of psu's providing reliable service for years and now being reported as unreliable by users in 2007.

Sparkle/Fortron units have traditionally been reported as the best bang for the buck psu, but it is the only psu I've purchased that ran 366 days and promptly lost the +12vdc rail. Allied psu's are reported to be junk but, I never had a problem with the forty or so units I currently use. </endrant>

Back to the originally scheduled thread...

Skip

http://skipcox.net

 

[wahnula]

In my home machines (for silence) I use only Nexus PSUs. Every other PSU I build (except that danged Antec) comes from

http://www.pcpower.com

When it comes to quality PSUs, they set the gold standard.

Tony

 

[SkipCox]

I agree wahnula...pcpower has been one of the top consumer choices for many years.

I'll take my chances with them any day.


Skip

http://skipcox.net

 

[pdb123]

Changed the Power supply and it worked.
Thanks for the advice.
Got one for abou $8 on Ebay,
I hope the fact its so cheap doesnt come back to bite me on the ass.
Thanks guys

 

[wahnula]

Changed the Power supply and it worked

If we were all playing a giant worldwide game of Clue, the card with Mr. Power Supply on it would be just about worn out.

Thanks pbd123 for reporting back with the solution and placing another arrow in the quiver for the power supply as a key problem component (mixed metaphors aside).

I hope the fact its so cheap doesn't come back to bite me on the ass.

It probably will, especially if it's a power user's PC, but at least now you'll now know where to look.

Tony