I have a CFL backlight connected to the 12V rail of my HTPC and controlled by a physical switch: The problem is, if I turn the backlight on while the PC is powered, sometimes the PC will hard reset. I suspect that powering up the backlight causes a voltage spike that will sometimes trigger short-circuit protection in the PSU. I was told that adding a large capacitor BEFORE the switch may get rid of the voltage spike when the backlight is turned on. From what I understand it should be wired like this: However, the spike still occurs sometimes. Does anyone here know if this is the right approach? The capacitor is not connected right next to the switch but a short distance away with jumper wires. Might that be the problem? Do I just need a bigger capacitor? Any help is appreciated, thanks!