A Pi 4 works from my notebook and one of my USB power blocks. There are problems.
My notebook has two USB 3 sockets next to each other with enough power for a Pi 4 but not enough for a Pi 4 plus a USB 3 disk. Some USB 3 power blocks have the same problem, the voltage drops too far when drawing significant power. Test both. Let them run for a while with something running to ramp up power usage in the Pi. The same setup may fail when you plug a disk into the Pi and start writing to the disk.
Half of my USB 3 cables drop the voltage too far. Use a good quality cable, preferably at least USB 3.1 because the USB 3 standard is rubbish.
My notebook has two USB 3 sockets next to each other with enough power for a Pi 4 but not enough for a Pi 4 plus a USB 3 disk. Some USB 3 power blocks have the same problem, the voltage drops too far when drawing significant power. Test both. Let them run for a while with something running to ramp up power usage in the Pi. The same setup may fail when you plug a disk into the Pi and start writing to the disk.
Half of my USB 3 cables drop the voltage too far. Use a good quality cable, preferably at least USB 3.1 because the USB 3 standard is rubbish.
Statistics: Posted by peterlite — Thu Dec 18, 2025 6:10 am