“The heat sync has sticky thermal-coupling pads attached to the bottom which connect to various important components on the Pi, and the installation instructions make it clear that these should not be removed once attached. This makes the installation a little unforgiving, so be very careful to get everything aligned correctly first. The component contains 2 pins which connect to holes in the Pi for alignment and attachment. I found this process a little fiddly since there is a bit more give in the positioning than I would like, and the pin clips are very stiff, making them difficult to attach once in position. But ultimately it's not too difficult to attach with some care, and Just Works after that. It is also designed to avoid getting in the way of any connectors on the board, which is certainly appreciated since it cannot be removed!
In operation, the fan itself is very quiet and usually doesn't run at all (it only runs when the Pi is under heavy load, and for a second during startup). For actually cooling the Pi down, it seems to do a decent job (though I haven't tested it thoroughly and I rarely push the Pi enough to turn the fan on for long)”
“I can't be sure that I needed this as so far it only comes on momentarily when my Raspberry Pi 5 boots up, however, at the cost, its hardly worth the trouble to find out.”
