ATX Power Supply Jumpers

ATX Power Supply Jumpers

Attempting to replace or repair your computer’s power supply unit (or PSU) is becoming increasingly easy, even if you don’t have advanced training or experience in working with computer hardware. A variety of different companies including both online retailers as well as local computer hardware stores now provide the necessary components to do some home repairs.

This provides some basic information on getting started using or updating the ATX power supply, whether replacing components or using a jumper to test or trigger a power supply unit to see if it’s working—however individual specifications differ between units and may require some specific attention.

The ATX form factor represents a specification system for the interconnection of your computer, your power supply unit and your processor or motherboard.

First introduced by the Intel Corporation in 1995, ATX (or Advanced Technology eXtended) specifies the connection of these components based on:

  • The physical dimensions of your computer.
  • The location of the mounting points on the computer chassis.
  • The input / output panel and the type of pin-out connector used.

It has gone through a number of different versions since its introduction, with subsequent versions offering improved efficiency and cost saving improvements.

Using jumpers to modify ATX Power Supplies

Although some experience is typically recommended for attempting repairs to your computer’s power supplies or modifying them, it is possible to alter an ATX power supply to turn it on without being attached to a motherboard.

This is useful if you wish to test whether the PSU is working or has any problems. For example, if your computer is failing to start under conventional methods, you may wish to test the power supply unit to determine whether the problem lies with it. This provides some basic instructions for a standard 20 pin type connector under the ATX specification.

  • First, unplug the power cord from the power supply unit as well as the motherboard.
  • Second, use a jumper to short out pins 14 and 15 on the 20 pin connector. These are the fourth and fifth pins from the top on the right hand side when looking at the connector, or the green to black coloured pins.
  • Then, plug in the power supplies cord to the electrical main just long enough to see whether it turns on the fan for the power supply unit. This allows you to determine whether or not a fault lies with the power supply unit—if the fan starts turning, the PSU is ok.

Basic safety for repairing or working on ATX Power Supplies Units

There are a few basic considerations for other repair, replacement or modification work on power supply units.

  • First, before attempting to replace any components, make sure the PSU is disconnected from the electrical mains.
  • It’s also important to remember that PSUs can carry a residual charge even after being disconnected, so it’s important to ground the unit safely before attempting to do any work, as this can deliver a nasty shock.
  • If at all uncomfortable with any of the repair work, don’t hesitate to consult expert technicians or speak to sales representatives to ensure you don’t risk damaging your computer.