Raspberry Pi Keeps Restarting - Power Supply? SD Card? What?

Woke up to find my HA web site unresponsive. It’s on a RPi 3B+

I was able to Putty in, and I was also able to backup my config folder using SMB. But then it restarted, and kept restarting after a varying amount of time. Eventually it began to restart so frequently that I couldn’t connect at all.

I assumed a bad SD card, based on everything I’ve read here. I re-installed a fresh image, hoping to pop it in, restore from backup, and be back to normal.

Nope. Still keeps rebooting. I can’t find another 3A power supply, so I’ve ordered one for overnight delivery. I did scrounge up a 32G SD card, but it’s a no-name brand. I’ll give it a shot putting the HA image on that next.

I figured I’d ask here and see if anyone has any other suggestions. I’m leaning toward the power supply. It’s rated at 3A but it’s a no-name brand. The SD card performed flawlessly for the re-format and re-image. And yes, I know, I should get off SD cards and go with a SSD or disk. But the immediate issue is getting back on line.

Is there something I’ve missed?


Here’s what I know so far. After almost two years of flawless operation, my RPi started rebooting repeatedly with a “low voltage” condition.

After trying several different 3A power supplies, and short, heavy USB cables, I found a combination which seems to work, but I still get the voltage warnings. I have a USB power meter and it never pulled more than .6A and the voltage never dropped below 5.18V. Even assuming a .1V drop through the cable, I see no reason the Pi should complain.

I’ve ordered a new power supply, but I’m beginning to suspect the Pi itself. I’ve been doing some searching and I’m not the only one who’s seen this.