Perform the following steps, in order, until power is restored or it is determined that there is a hardware failure:
1.Disconnect everything from the computer, including the power cord.
2.With the power cord disconnected , press the power button on the front of the computer for five seconds. Plug in the power cord and test to see if the computer can turn on. If not, continue using these steps.
NOTE: If the power supply fan makes an inconsistent grinding sound or stops and starts erratically, replace the power supply
3. With the power cord removed, flip the red voltage selector switch to the opposite position. Wait about five seconds, and then switch the red voltage selector switch back to its original location. Ensure that the voltage selector switch is on the correct setting, 115V for North America.
Performing this step ensures that the voltage switch is engaged and set correctly for your country/region.
4. Plug in the power cord and test to see if the computer can turn on. If not, continue using these steps.
5. Plug a lamp into the same outlet to see if the wall outlet has power. Try the computer in a different outlet in order to eliminate the outlet as a possible source of the issue. Test both to see if the wall outlets have power.
6. Remove all extension cords, power strips, surge protectors and any converters that remove ground. Plug the power cable directly to the wall outlet. Test for power. If this fixes the issue, find the device that is causing the issue and do not use it.
NOTE: If you find the device that was causing the problem was a surge protector, resetting a breaker or fuse on the surge protector may fix the issue.
8. Remove all attached devices except for keyboard, mouse, and monitor.
9. Remove any internal component that was recently added, such as video card, memory, CD, DVD, and hard drives. An added device may take more power than the power supply is rated for. If the problem goes away when the component is removed, the only option is to upgrade the power supply to power supply with a higher wattage rating.
10. Check the power switch:
a. With the power cord disconnected, press the power button on the front of the PC. The button should release easily and not stick in the socket.
- If the button sticks, it should be replaced or serviced.
- If the power button does not stick and appears to be functioning, continue using these steps.
11. With the power cord disconnected, remove the case or side panel.
- Follow the wires from the power button on the front of the computer to their connection on the motherboard.
- Look at the power switch cables connected to the motherboard. If the cable has become disconnected, connect the power switch cable connector to the connector on the motherboard.
- Replace the side panel, plug in the power cord and test to see if the computer can turn on. If not, continue using these steps.
12. Find the defective part:
- With the power cord disconnected, remove the case or side panel.
- Disconnect all power cable connectors from their connectors on the motherboard and from the back of internal devices (the back of drives). Make sure to label or remember where each cable connects for future reference.
- Replace the side panel, plug in the power cord, and examine the light on the back of the power supply:
13. If the LED is on solid and is not flashing, the power supply is probably good and the problem is most likely caused by a defective component (processor, memory, PCI card) or a defective motherboard. Have the computer serviced, or remove the components and replace them, one at a time, to find and replace the defective component.
14. If the LED is still flashing (it should not flash with all connectors removed), plug the power cable into a different power outlet that is known to be good. If the LED still flashes, the power supply should be replaced.
15. If the LED light is now off, plug the power cable into a different power outlet that is known to be good. If the LED stays off, the power supply should be replaced.
NOTE: If an electrical storm or power surge has recently occurred, then it is more likely that the power supply, the modem, or motherboard is damaged and requires replacement.