pc won't power on

[davew]

a friend has just dropped off a hp pc that won't power on, there is a flashing green light on the power supply and also one on the motherboard, if i unplug the power connector to the motherboard the one on the power supply turns solid green and plug it back in it boots fine, but if i turn it off and back on again i get the flashing green lights and it won't boot unless i pull the motherboard connector off and put it on again, looks like a dodgy connection somewhere ,i've tried wiggling the power connection to the motherboard when the light is flashing but it makes no difference

 

[Jaffa_Cake]

looks like a dodgy connection somewhere

Or just a crap PSU. If the motherboard works fine then it sounds like the PSU is to blaim.. Can you test another one in it? Or just wire yours into the other pc without taking it apart

 

[davew]

cheers i'll try swapping the psu and see what happens

 

[davew]

ok tried one of my psu's in and it seems to work ok, strange thing is with the old psu fitted there must be power to the motherboard as there is a green light on, but it seems not enough power to start the pc up.

 

[firewallblocked]

I have an antec power supply tester and my mates pc would not boot although the switch was lit and a light was on on the motherboard. Tested the psu with the psu tester and the +5v +12v +3.3v & -12v were all showing as faulty.

The tester won't always tell you the psu is dying when your system still boots but is unstable, but it will show critical faults.