Peripherals LED keeps turning on by itself even my PC is off.

TukangUsapEmenq · May 3, 2023

Well, I live in a boarding house, which is a former industrial mess complex that's only have one plug that I connected everything on my room (PCs, electrical stove, fan, router, etc.) using an extension cable (high-quality ones). Room's still using fluorescent lamp using ballast.

In (a lot) of cases, every time I turn on/off the lamps on my room, my PC peripherals' LED (it's a keyboard and mouse with RGB) would've turn on by itself, even if the PC is turned off. My assumptions the lamp's ballast causing the PC to act weirdly like so to turn on the power on the USB ports.

To be fair, my extension doesn't include the ground wiring, as it's only a (still, a good quality) 2x1.5mm cable. I would want to get the 3x1.5 ones but... I have to get it online as my country electrical shops barely sells any wires with 3 cores. I am well aware of the hazard of this, and yes I plan to change the cable to 3x1.5mm later on.

Yet, back to topic. I don't know what's causing the LED to turn on, and I have to unplug the USB cable for the keyboard every time it happened, so... Can anyone enlighten me? Will changing my extension cable to include grounding will solve this as some power would've 'trapped' because there's no ground?

Bismut · May 3, 2023

This is worrying on so many levels, wow.
I would try proper grounding first, but some Motherboards will just keep the PSU running too, which could cause your peripherals to light up. Does your phone charge when you plug it in?