The C64 power supply will kill your machine

This is the most important thing any C64 owner can learn. The original power brick is a machine killer. Do not trust it. If you value your Commodore 64, unplug that old brick and do not power on until you have read this. Here is the failure mode. Inside the original supply, the part that lowers the voltage can fail as it ages. When it fails, it does not simply stop. It sends too much voltage into the computer. That surge fries the chips inside, and some of those chips are rare and hard to replace today. One bad power-up can turn a working C64 into a dead one in a second. The cruel part is you get no warning. It can happen the very next time you switch on. SAFETY NOTE: the power brick plugs into the wall and handles mains voltage, the same deadly voltage as a socket. Do not open the sealed brick to inspect it. Just retire it. The fix is simple: buy a modern replacement supply. New ones are built to shut themselves off if the voltage climbs too high, so they protect the computer instead of killing it. Search for a modern Commodore 64 power supply, and pick one that mentions over-voltage protection. Several trusted makers sell them. If you want to keep using an original brick for the look, there is a middle path. A saver adapter sits between the old brick and the computer. It watches the voltage and cuts power the instant it spikes, saving your chips even if the brick fails. Search for a C64 power supply saver. It is cheap insurance. Most people say do both if you can: a good modern supply, plus keep the old one only for display. See this machine's spec sheet in the library, including its voltage needs.