First, check the power source and cables by ensuring connections are secure, testing outlets, and swapping chargers or power cables. 2. Look for signs of power like fan movement, lights, or beeps; if absent, suspect power supply, motherboard, or power button issues. 3. For desktops, test the PSU using the paperclip test to see if it powers on. 4. Reset components by disconnecting peripherals, testing RAM sticks individually, and resetting CMOS to rule out hardware or BIOS issues. 5. Inspect for physical damage such as burnt components, bulging capacitors, or dust buildup, and clean or repair as needed. 6. For laptops, perform a hard reset, check the DC jack for damage, and consider professional repair if internal circuits are faulty. When troubleshooting fails, replace the PSU first in desktops or consult a technician for laptops, as most no-power issues stem from fixable power-related causes.

When your computer won’t turn on, it can be stressful—especially if you rely on it for work or personal use. But before assuming the worst, take a systematic approach. Most "no power" issues stem from simple causes that you can diagnose and often fix yourself. Here’s how to troubleshoot step by step.

1. Check the Power Source and Cables

Before diving into internal components, confirm the basics:

• For desktops:

  
  • Make sure the power cable is securely plugged into both the wall outlet and the back of the power supply.
  • Try a different power outlet or power strip. Test the outlet with another device (like a lamp) to verify it’s working.
  • Check if the power supply switch (on the back) is turned on.
  • Inspect the power cable for damage. If possible, swap it with a known working one.

• For laptops:

  • Plug in the charger and ensure the connection is secure at both ends.
  • Look for LED indicators on the charger or laptop. If none light up, the issue may be the charger or battery.
  • Try a different charger (with the same voltage and connector type) to rule out a faulty adapter.

? Pro tip: If the laptop still won’t charge, remove the battery (if removable) and try running it on AC power only.

2. Look for Signs of Power

Even if the screen is black, your computer might actually be getting some power. Watch for clues:

• Fans spinning (even briefly)
• Lights on the motherboard or case
• Hard drive or SSD activity
• Beep codes or LED error codes (on some motherboards)

If you see any of these, the issue might not be power delivery—but something else like display, RAM, or boot failure.

But if nothing happens when you press the power button (no lights, no sounds, no fans), the problem is likely:

• Faulty power supply (desktop)
• Failed motherboard or power circuit (laptop)
• Bad power button or internal wiring

3. Test the Power Supply (Desktops Only)

A failing PSU is a common cause of no power. You can test it without special tools using the paperclip test:

1. Unplug the PC and open the case.
2. Locate the 24-pin motherboard connector on the PSU.
3. Take a paperclip and bend it into a “U” shape.
4. Insert one end into the green wire pin (PS_ON) and the other into any black wire pin (ground).
5. Plug the PSU back in and flip the switch on the back.

? If the PSU fan spins, it’s likely delivering power.
? If nothing happens, the PSU is probably dead and needs replacement.

?? Caution: This test only checks if the PSU turns on—not if it delivers stable power under load. Use a PSU tester for more accuracy.

4. Reset or Disconnect Components (Desktops)

Sometimes a faulty peripheral or RAM stick can prevent booting. Try a minimal boot:

• Disconnect all non-essential devices (USB drives, external hard drives, etc.).
• Remove all RAM sticks except one. Try each slot and stick individually.
• Disconnect the GPU and use onboard graphics if available.
• Unplug drives (SSD/HDD) and see if the system at least powers on and beeps.

If the system now powers on, reconnect components one at a time to find the culprit.

Also, try resetting the CMOS:

• Unplug the PC, remove the CMOS battery for 5 minutes, then reinsert it.
• Or use the CLR_CMOS jumper on the motherboard (check your manual).

This can resolve issues caused by corrupted BIOS settings.

5. Check for Physical Damage or Overheating

Inspect inside the case for:

• Burnt smells or scorch marks (especially on the PSU or motherboard)
• Leaking or bulging capacitors
• Dust buildup blocking airflow

Overheating from poor ventilation can cause shutdowns or failure to start. Clean fans and vents with compressed air.

Also, ensure the CPU is properly seated and the cooler isn’t putting too much pressure on the motherboard.

6. Laptop-Specific Fixes

If your laptop won’t turn on:

• Hard reset: Unplug the charger, remove the battery (if possible), and hold the power button for 30 seconds. Reconnect and try again.
• Check the DC jack: Wiggle the charger plug—if the connection is intermittent, the jack may be damaged.
• Motherboard or charging circuit failure: If the charger works but nothing powers on, the internal power circuit or motherboard may need professional repair.

When to Seek Help

If you’ve gone through these steps and still get no response:

• For desktops: The motherboard or PSU is likely faulty. Replace one at a time (start with PSU).
• For laptops: Internal issues like a dead motherboard or power management chip usually require a technician.

? Bottom line: Most "won’t turn on" problems are power-related and often fixable with simple checks. Don’t assume it’s dead—test methodically.

Basically, start simple, rule out the obvious, and work your way inward. Most issues aren’t as bad as they first seem.

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