Electronic – White glue on circuit board?

circuit-designpower supply

Took apart an Apple TV due to no power from the smps and its like 80% covered in a white rubbery adhesive.

I'm used to seeing this stuff (or similar) on bigger components like electrolytic caps to minimize vibration but I'm curious it's purpose on the bottom of the board where it's all smd? Other than to make it really annoying to chip away to test components

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Best Answer

Its a type of RTV silicone adhesive that helps prevent component vibration, larger components like capacitors are normally secured by it as any excess movement in them can add to the chances of broken solder joints. I can only imagine its been added here to help secure the transformer etc but has been applied in a really shoddy way