Laptop power supplies can cause many unusual issues including poor battery life, erratic behavior and corrupt data. A failing power supply may become overly warm or generate buzzing or whining sounds. Any power supply noise should be immediately investigated.

Laptop Power Supplies

Laptop power supplies convert AC power from the wall to DC at the laptop. Several components can fail inside the power supply through heat, moisture or impact damage.

Power Supply Failure

Power supplies for laptops usually fail due to electrical issues, such as power spikes or lightning strikes, as well as low power situations during brown outs. Failure also occurs through damage at the laptop connector, which can become bent or broken if not treated carefully.

Power Supply Symptoms

A failing power supply may become hot to the touch, fail to charge the battery, or make noises such as buzzing or whining sounds. Erratic behavior or trouble starting up the computer can also be signs of trouble.

Repairing Power Supplies

There are many small electrical components inside a laptop power supply, including capacitors which can deliver an electrical shock if touched. Attempting to repair a power supply is not recommended.

Replacing Power Supplies

New and used power supplies for laptops are easy to find and are inexpensive. Check the manufacturer's site for replacement parts first. If the manufacturer's part is too expensive, new and used parts are readily available at online auction sites. Universal power supplies are also available from many electronics stores.

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