Symptoms
- Small cylindrical capacitors on the motherboard have a domed or bulging top instead of flat
- Brownish or crusty residue visible around the base of a capacitor
- System has become increasingly unstable, with random reboots or failure to POST
- Motherboard is several years old, especially if it ran hot or was in a poorly ventilated case
Likely causes
- CommonCapacitors degrading naturally with age and heat over years of useThis was especially common in a well-known wave of bad capacitors in the 2000s but still happens with age generally.
- PossibleChronic overheating accelerating capacitor wearPoor case airflow or a hot GPU/CPU nearby can shorten capacitor lifespan.
- PossibleA power surge or electrical event damaging capacitorsA single bad event can cause immediate, visible bulging.
What to do
- Power off and unplug the PC before inspecting the motherboard.
- Visually inspect the small cylindrical capacitors near the CPU socket and power delivery area for doming, bulging, or leakage.
- Do not attempt to use the system further if bulging capacitors are found, since failure can worsen suddenly.
- Back up any important data from the system's drives while it's still able to boot, if it does.
- Motherboard-level capacitor replacement is a specialized soldering repair, generally not practical for most people at home.
- Plan to replace the motherboard, since a board with visibly failing capacitors is not reliable long-term.
Tools and parts
Replacement motherboardSearch: “motherboard matching your CPU socket and RAM type”
When to call a pro
Bulging capacitors mean the motherboard should be replaced; a specialized electronics repair shop can occasionally replace individual capacitors, but this is a niche and often not cost-effective repair.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.