P
PC FIX
Power

Desktop PC will not power on

If the current symptom is closer to “no response when pressing the power button,” first check for problems with the power strip, outlet, power cable, or power supply failure. The key is to reduce unnecessary disassembly by checking the external power supply, power supply, and motherboard in that order.

Solving Order
We've organized the methods starting with the simplest and least expensive ones. Please check the solutions one by one, starting from the top.

Do you have these symptoms?

  • Nothing happens when I press the power button
  • PC power indicator does not light up
  • The fan doesn't even turn on.
  • Computer power unresponsive

main causes

  • Power strip, outlet, and power cable problems
  • Power supply failure
  • Motherboard power connection problem

How to solve

Please check them in order from the top. If the issue is resolved, you do not need to proceed to the next step.

1

Check the outlet and power cable

The first thing to rule out is that the power itself is not supplied.

Difficulty Easy time 3-5 minutes cost 0 won
  1. 1Check whether the power strip switch and wall outlet are in good working condition.
  2. 2If possible, unplug the power strip and plug directly into a wall outlet.
  3. 3Reconnect the PC power cable from both sides and test if a good cable exists.

confirmation point

After these steps, see if the “Nothing happens when I press the power button” symptom decreases or disappears. If there is no change, check for possible problems with the power strip, outlet, or power cable in the next step.

2

Check the switch on the back of the power supply

If the desktop power supply's I/O switch is turned off, the PC does not respond at all.

Difficulty Easy time 1 minute cost 0 won
  1. 1Locate the power supply switch on the back of the PC.
  2. 2Make sure it is in the direction indicated by I.
  3. 3Even if your old power source has a voltage selection switch, don't change it arbitrarily.
3

Discharging residual power

The power protection circuit or the motherboard may be temporarily unlocked.

Difficulty Easy time 3 minutes cost 0 won
  1. 1Unplug the PC power cable.
  2. 2Press the power button for about 15 to 20 seconds.
  3. 3After 1 minute, reconnect the power cable and try turning it on.
4

Disconnecting USB and recently added components

The power may not come on due to a short or defective external device or new part.

Difficulty Moderate time 10-20 minutes cost 0 won
  1. 1Disconnect all USB and external devices.
  2. 2If there are any parts that were recently added, check the installation status with the PC completely turned off.
  3. 3Verify that power response returns in minimal configuration.
5

Checking the power supply and motherboard

If it continues to be unresponsive, the possibility of a problem with the power supply, power button, or motherboard power circuit increases.

Difficulty Advanced time 30 minutes or more cost Parts/repair costs may apply
  1. 1Do not open the inside of the power supply.
  2. 2Proceed only when cross-testing is possible with a power that has been confirmed to be operating normally.
  3. 3If you are unsure, have the power supply diagnosed at a service center or repair shop.

Precautions

Dangerous voltages may remain inside the power supply even after the power is unplugged. Do not disassemble the power supply itself.

Frequently Asked Questions

We've put together a list of things we frequently check regarding this issue.

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