use a psu without a motherboard

  djbenny 14:40 01 Nov 2005

i hjave looked n looked but vcant find instructions on where to put the wire on the atx connection for the psu to work without the motherboard

  PaulB2005 14:41 01 Nov 2005

Why do you want to do this?

  djbenny 14:42 01 Nov 2005

to test the psu and maybe run something straight from the psu

  €dstowe 14:44 01 Nov 2005

Running a computer PSU without a load on it (motherboard) is a sure fire way to get it to burn out. This burnout can be spectacular so, if you try it, stand well away.

  djbenny 14:45 01 Nov 2005

i have done it in the past safely but i have forgotten which pins in the socket need wiring

  djbenny 14:48 01 Nov 2005

i have managed to find instructions

  Zaphod Beeblebrox 14:48 01 Nov 2005

i wouldnt advise running a psu without a load on it especially if it is a cheap one it may well cause the psu to fail

  Arnie 19:38 01 Nov 2005

Remove the power supply from the computer.

Connect a 10 ohm 10 Watt load resistor between:

Pin 4 (+5V) & Pin 5 (Ground).

This places a suitable load on the supply.


Pin 14 (Power on) & Pin 15 (Ground).

This link kicks the PSU into action on switch on.

BTW Pin 9 supplies the standby current when the PSU is normally connected to the motherboard.
Approx 700mA when the computer is switched off at the panel.

If you do not further intend to use the PSU in a computer again, cut off the connector from the loom and use a choc strip to make the connections.

Do not open the case of the PSU. This will expose the mains supply. The secondaries are all isolated low voltages and are safe to use.

The above method can also be used to test ATX supplies if removed from the computer.

  The Spires 20:01 01 Nov 2005

Arnie, noted & stored. :-)

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