Identify and Replace Blown Motherboard Capacitors

Problem overview

Your computer experiences random crashes, fails to POST, or exhibits extreme instability. Upon visual inspection, you notice small cylindrical components on the motherboard that look deformed or are leaking fluid.

Common causes

• Aging components reaching the end of their lifespan
• Poor quality electrolytic capacitors
• Extreme internal case temperatures
• Dirty power delivery from a failing PSU

Solution 1: Inspect and identify the damage

1. Unplug the PC and open the side panel. Use a flashlight to inspect the motherboard.
2. Look at the tops of the electrolytic capacitors (the small cylinders). A healthy capacitor has a completely flat top.
3. If the top is domed, bulging, or has a crusty brown substance leaking from the cross-vents, it is blown.
4. Read the side of the blown capacitor and note its voltage (e.g., 16V) and capacitance (e.g., 1000uF).

Solution 2: Desolder the blown capacitor

1. Remove the motherboard entirely from the case.
2. Locate the solder joints for the blown capacitor on the underside of the board.
3. Apply a soldering iron to the joints while gently pulling the capacitor from the top side.
4. Use solder wick or a desoldering pump to clear the remaining solder from the through-holes.

Solution 3: Solder the replacement

1. Note the polarity of the capacitor. The side with a white stripe and minus symbols indicates the negative lead.
2. Insert the new capacitor, ensuring the negative lead goes into the negative hole (usually marked with a white half-circle on the motherboard silk screen).
3. Solder the two pins to the bottom of the board and snip off the excess lead wire.
4. Reinstall the motherboard and test the system.