Whenever a Raspberry Pi is sent back to the distributor as a faulty unit, someone in the chain (we at the Foundation, the distributors, and now the factory in Wales) tests the unit to see what was wrong with it, so we can try to eliminate any problems in later production runs. We get very few returns, and I’m very happy to be able to say that nearly half of the returns we do get involve Raspberry Pis which don’t actually have any problems at all; in these cases what’s usually going on is that the user hasn’t flashed the SD card correctly (or, sometimes, at all!), or hasn’t connected it to a display device properly.

But occasionally it’s been challenging to find out what’s up with a broken unit. In these cases, we sometimes ask the customer to send us the power supply they’ve been using (and, from time to time, some other peripherals too) so we can dig a little deeper.