Is it secure to turn off the power supply after shutting down?
Is it secure to turn off the power supply after shutting down?
I understand everyone's view. Avoid this. I believe it could cause capacitors to degrade, possibly keeping them charged even when the computer is off. It's unclear if they drain during normal shutdowns, but frequent charging and discharging might affect their lifespan.
A companion arrived with his machine since the power button on his ATX PSU was emitting "fizzing" noises and the computer refused to start. He had flipped the switch several times daily, and after five years of operation, the device had finally given up. I suggested he replace the power supply unit.
Upon examining the damaged switch, it appeared the metal contacts were partially melted due to repeated arcing, while the plastic casing was blackened. Standard ATX PSUs usually operate within current ranges of 20A to 100A, even with an NTC thermistor.
Typical ratings for these switches are around 10A or 16A AC (continuous), but frequent surges up to 100A can eventually degrade the contacts. I warned my friend against constantly toggling the switch, yet he persisted. He opted for the most affordable replacement available, which could fail sooner.
If all my systems remained plugged in and in standby mode, the Vampire power draw would likely surpass 200W. At about US $0.33 per kWhr, I’m unwilling to waste resources unnecessarily. Ultimately, I simply turn off my computers and monitors once they’re done for the day.
It seems Asus might be producing faulty power supplies. Considering their other products and the problems with motherboards, I prefer to avoid them. They were decent before, but asrock appears to offer better quality now.
misinformation
the sole motherboards with power reaching the cmos battery are the industrial models equipped with rechargeable batteries.
I believe the issue is a "capacitive surge," and the large sudden current that damages switch contacts occurs when power is switched on because of arcing. The main capacitor in an ATX PSU begins at zero Volts and quickly builds up to 340V DC (from my local 240V AC source), resulting in a high surge current of up to 100A. Inductors might contribute to switch wear when the PSU is turned off, releasing stored energy and leading to arcing across switch contacts as they close. I've experienced switches in inexpensive 13A mains sockets failing after two years of switching ATX PSUs on and off, similar to some ATX models. The lower quality the switch, the faster it tends to fail. Switch contacts also seem to deteriorate when relays are repeatedly cycled with ATX PSUs, lasting only a few years before failure. This isn't limited to Asus PSUs; many brands exhibit high inrush currents, particularly in regions using 230V AC. Here are some PSU reviews I found: - Seasonic 750W PSU: - Corsair 550W PSU: - Thermaltake 1200W PSU: I've observed these models from three different manufacturers all delivering a peak of 86A at the switch when tested at 230V. It seems there are better options with lower surge values, and some even higher ones. I own several Asus motherboards—one with a 3800X (2018) and another with a 7950X (2022)—both still functioning properly. I also have Gigabyte, ASRock, MSI, SuperMicro, Intel, Dell, and HP boards. No clear favorites here.