Ask any repair technician for their most embarrassing fix and you will hear the same list: a dead wall socket, a switched-off extension board, a power supply whose own switch was knocked off during cleaning. These are not rare jokes — they are a daily percentage of will-not-start complaints. This page walks the whole chain, wall to PC, in five minutes.
Electricity reaches your PC through a chain of small, forgettable links: socket, extension board, cable, the supply's rocker switch, and only then the button you press. A break anywhere in the chain looks exactly like a dead computer. The chain is also the cheapest thing to test — free, fast, and needing no tools but a phone charger. Run it in order, outside-in, before the cabinet comes open.
Plug a phone charger or a lamp into the exact socket the PC uses. If it does not work either, your computer is innocent: check the switchboard for a tripped breaker, especially after a storm, a power cut, or a heavy new appliance joining the circuit. Sockets and their wall switches also wear out silently in older buildings — the switch feels fine and passes nothing. One trusted small device answers the whole question in ten seconds.
Extension boards and spike guards have their own switches, fuses and failure ages, and they sit under desks where feet and vacuum cleaners visit daily. A board can power the monitor (making everything look normal) while its other sockets have died, or its switch can be half-pressed by a bag strap. The decisive test is brutal in its simplicity: plug the PC directly into the wall socket, once. If it starts, you have found your culprit and your shopping list is a new extension board — not a new PC part.
Desktop power supplies carry their own small rocker switch next to the cable socket, marked 1 and 0. It gets knocked to 0 when the PC is carried, tilted for cleaning, or pushed back against a wall. A surprising number of dead PCs are exactly this. Feel for it, set it to 1, and try the front button again. One honest caution: very old supplies also carry a small red voltage selector (230/115). Do not experiment with it — a wrong setting on the wrong mains can damage the supply. If it was never touched, leave it alone.
The kettle-style power cable loosens at the supply end more than anywhere — it hangs by its own weight and gets nudged by feet and cables. Pull it out, push it back until it seats with a firm stop, and do the same at the wall. If you have a second cable (the monitor usually uses the same type), swap it in as a test: cables do fail internally while looking perfect. On laptops, the equivalent is the adapter brick itself — check its joints, its light if it has one, and try a second socket before suspecting the laptop.
If the socket works, the direct-to-wall test changes nothing, the rocker is on and a known-good cable changes nothing, then the chain has honestly cleared itself — the break is inside: the power supply or the board. Say so plainly and move to the next level of checks (the drain trick and the reseats in the core guide). What you have bought with these five minutes is certainty: nobody will later fix this PC by flipping the switch you already proved good.
The video runs this exact chain on a dead PC — socket, board, switch, cable — before a single screw comes out. Watch how often the boring answer is the true one.
▶️ Watch Full VideoYes. The monitor and PC often sit on different sockets of the same extension board, and boards fail one socket at a time. Test the PC's exact socket with a phone charger, and try the PC plugged directly into the wall. The monitor lighting up proves its own link only, not the PC's.
No. The rocker switch simply cuts power to the supply; a PC that sat with it off is unharmed, just unpowered. Flip it to 1 and start normally. The switch gets knocked during moving and cleaning often enough that technicians check it before they check anything else.
Then the chain has done its job — it has cleared itself. Move one level in: drain the leftover charge (unplug, hold the power button 20 to 30 seconds, retry), then the reseats in the core guide. If there is still no standby light and no response, the power supply itself becomes the prime suspect and a swap test is the honest next step.