Quote: Originally Posted by pebbly
Quote: Originally Posted by alphanumeric
The power switch on most PC cases is a momentary, normally off, switch. The contacts are only made when you press the button and open again when you take your finger off. The reset button, if your case has one, should be the same. So you could just swap the connectors on the motherboard and use the reset button to turn it on. Either temporarily or permanently.
Surely the on/off must be latched ?
The power switch on the actual power supply is, that switches the AC mains off.
The power switch on the case isn't though. The way it works is the Auxiliary +5v supply in the power supply, that is always on, sends 5 volts to the motherboard to power the circuit that turns every thing on. When you press the front panel power button on the case, that signals the motherboard to power on the power supply fully. Depending on how the BIOS is set, pressing it again for 4 seconds turns it off again. It can be 4 seconds or an instantaneous power off. Its just a pulse while the button is held pressed. If you used a latched switch your PC would just cycle on and off over and over again.