Case Study: HP Pavilion - A MOSFET Burnt Into the Board

The burnt MOSFET area of an HP Pavilion seen through a microscope

Device: HP Pavilion laptop
Booked in: for diagnostics
Diagnosis: a MOSFET had burnt and fused into the board’s laminate
Repair: carbon cleaned out of the laminate, tracks rebuilt, MOSFET, capacitors and resistors replaced
Turnaround: in one day, working and collected the next

A burnt component is usually a straightforward swap. This one was not. The MOSFET had burnt so hot that it fused with the fibreglass layers of the board beneath it.

What We Found

Burnt laminate turns to carbon, and carbon conducts. Soldering a new part on top of it would have left a leak path under the component, so the damage underneath had to go first.

The Repair

We cleaned the carbon out of the laminate and rebuilt the damaged tracks. Then we fitted a new MOSFET and replaced the capacitors and resistors around it.

The Outcome

The laptop worked, and its owner collected it the day after it came in. A board like this is often written off as scrap. Here, it needed one careful repair.

Burnt area around a MOSFET on an HP Pavilion motherboard — The burnt area on the board

The same area of the HP Pavilion motherboard during the repair — The same area during the repair

More on board-level repair and HP laptop repair.

Written by

Marcin Skwiercz

Founder & Director

Running Fixfactor since 2014 with a hands-on background in microsoldering and board-level repair. Today focused on growing the business, tracking industry trends, and making sure every device gets the attention it deserves.