PC switched off but red light shows

  billy 19:42 28 Apr 03
Locked

My PC just switched off (I am writing this from asnother one). Mains lead is OK and I have taken PC side panels off and I can see a red light on motherboard. As I switch on and off the fan moves a little bit so it looks like power is getting in but PC will not switch on. Any ideas?

  -pops- 19:50 28 Apr 03

There may be a switch preventing operation with the side panel removed.

  billy 20:03 28 Apr 03

Thanks, but does not work with side panels attached either.

  rickf 20:48 28 Apr 03

Is this a new pc and have you just noticed this prob. The reason I say this is that it may be the connector is connected the wrong way round to the m/b

  DieSse 21:25 28 Apr 03

Yes, there should be a red light on the board when the pug is in. Without power on the motherboard, the on/off switch (which in reality is a sort of super-standby switch) wouldn't work. Think of the on/off switch on a VCR - when a VCR is off, you commonly still get a display on the front panel.

However, you clearly have a problem if the system will not switch on. This could be almost anything - power supply - motherboard - plug-in card - processor - RAM - etc. To start troubleshooting, take everything out of the system except the bare minimum (you need at least - processor - one RAM module, and graphics card).

DO NOT take out items when the power lead is plugged in - unless there is a proper power switch on the power supply, and it's switched off, or you've turned off at the main plug - as you may damage them

  DieSse 21:27 28 Apr 03

When I say take out - for the drives you need only disconnect the power plugs.

  billy 21:46 28 Apr 03

Thanks for the suggestions which I will try. Before that, in answer to one suggestion, the Pc is a few months old (eBay so no warrenty) and was working fine. Whilst i was using it, it suddenly switch off i.e. screen went black and all activity stopped, so it was not a Windows shut down but like a loss of power.

When I press theon switch the fan twitches for ~1sec but no other sign off life. If it was RAM etc I would have thought the PC would have gone through some sort of power on check before noticing something was amiss. Any other ideas or shall I unplug the non-esseantials and try again?

  DieSse 23:12 28 Apr 03

Many faulty items, including RAM, can actually stop the system powering up - depending what's faulty with them. My number one guess from the way you describe it, would be a faulty power supply - but that's by no means certain.

  billy 07:20 29 Apr 03

Do you think it could be the power supply as there is a red light on the motherboard?

  billy 07:21 29 Apr 03

Not quite finished.......Is there any way I can test the power supply?

  Inverjazz 08:21 29 Apr 03

Remove everything except the power supply connector from the mother board. If there is still no sign of life from the power supply when you switch on it is almost certainly faulty.

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