The computer power is pushed, and the power light is continuously blinking, you see power monitoring leds are ON, and fans are working. But computer does not proceed to the OS boot, and even does not go to the BIOS. The computer monitor is essentially blank.
Based on the Dell users manual description the following problem points out on the power distribution failure inside the computer, while the computer does receive the electrical power from the power outlet.
Unfortunately, the problem has multiple explanations, and there are many things that can go wrong in its relation. Therefore, I will propose the following troubleshooting plan, starting from easy-to-do items and continuing to more complicated. Following every step, verify the computer performance. This way, you will know exactly, what the problem source is.
1. Check the power selection switch at your computer and ensure that the voltage selection is set properly to match the AC power at your location. Switch it back and force to ensure that it is indeed at the right position.
2. If you use UPS, reset it.
3. Try different power outlet to ensure that the problem is coming not from your external power supply.
4. Perform the computer “cold reboot” - shut it down, wait 5 minutes, and turn it again.
5. Shut down your PC, open the case, and verify all the cables are connected properly. Ensure that the processor power cable is securely connected to the system board.
6. Examine all your USB ports (front & back) for pins that are bent or pushed in and fix any that are bent. This appears to be the most frequent reason of the problem appearance.
7. Reset 3V battery on the Motherboard.
8. Replace 3V batter on the Motherboard.
9. Remove one-by-one all the nonessential hardware elements in the computer by disconnecting them from the motherboard, like non-essential boards, Floppy, DVD, network cards, etc.
10. Blow carefully with air blower inside the computer case. That will ensure that no pieces of metal or debris could cause the short circuit.
11. Swap the power supply in from another PC. Dell claims the power supply replacement is the #1 solution to this problem.
12. If there is no improvement, there is a good chance that the Motherboard should be replaced. Several users reported that the Motherboard was a core source for the problem appearance. But, in most cases, it means that it might be easier and cheaper to shop for a new computer.