A £300 Ubiquiti 16-port PoE switch was rescued from the bin for roughly £5 in parts. The failure was visible immediately: a Broadcom BCM5911 controller IC had a chunk of its plastic packaging physically missing, and downstream components including multiple MOSFETs and a diode were shorted dead. Four ports and their PoE function were completely gone.
The real obstacle was sourcing the BCM5911. Digikey and Mouser no longer stock it. A replacement turned up on AliExpress for £1.84, with all the usual uncertainty about whether it would be salvage, counterfeit, or a factory reject. It was none of those things. The chip was legitimate, and all four dead ports came back online, including powering a PoE camera.
The full repair video by Buy It Fix It is worth watching for the diagnostic process, not just the outcome. The methodical probing of shorted MOSFETs before even touching the Broadcom IC shows exactly how to trace damage from a single catastrophic event across a board. The switch, which carries 16 Ethernet ports and 2 SFP ports, is back in service.
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