I recently received my HiFive Unmatched board and had it booted and running for a few days. I turned it off overnight, and then this morning when I pressed the power button on the case, the fan turned on, I heard a “pop” sound, and then it turned off.
I’ve been working on diagnosing the problem, and if anyone else has suggestions, I would appreciate it!
Things I’ve tested:
The power supply I was using seems to be dead. When I connect the green/black wires on the main ATX header it doesn’t turn on.
When I connect another power supply to the HiFive board, it doesn’t turn on . This power supply turns on when connecting the green/black wires, but it’s old and I’m not certain that it’s fully functional.
I’ve visually inspected the board and don’t see any obvious blown caps, etc.
My questions are:
Has anyone else experienced a failure like this?
Is there any other ways to diagnose whether the board is completely dead?
Assuming the board died, is there any warranty/RMA process? I bought the board via crowd supply.
It seems like this ATX power supply could be bad based on your experiments. You may want to avoid using it.
Here are some ideas to help diagnose the issue:
Inspect the board for damaged devices such as chips, traces, and capacitors.
Check the board for loose hardware such as metal screw rolling on the surface.
Remove all socketed devices and cables: PCIe, USB, micro USB, SD card - Everything except the CPU fan.
If you have an ohm meter you can check for power supply shorts to ground. J22 has many internal power supplies and mounting holes are ground. Check ATX power supplies 3.3V, 5V, 12V for shorts to ground underneath the connector.
Connect only the ATX power supply and try to power on the board again.
Make sure you’re pressing the power button instead of the reset button to power on the board.
Was the board in a chassis or were you using standoffs? Make sure there’s not something electrically conductive touching the board.
Can you send information about the original (pop) power supply and a pic of the ATX connector/cable?
Inspect the board for damaged devices such as chips, traces, and capacitors.
I don’t see anything obvious.
Check the board for loose hardware such as metal screw rolling on the surface.
Seems fine. I’ve tried it both in the enclosure and out of the enclosure.
Remove all socketed devices and cables: PCIe, USB, micro USB, SD card - Everything except the CPU fan.
Tried that… nothing doin’
If you have an ohm meter you can check for power supply shorts to ground. J22 has many internal power supplies and mounting holes are ground. Check ATX power supplies 3.3V, 5V, 12V for shorts to ground underneath the connector.
Ah… there it is! The 5V line is shorted. Any hints where there may be a broken trace/cap?
Connect only the ATX power supply and try to power on the board again.
Tried this before (4). Unsurprisingly, after discovery of the 5V short, it didn’t work.
Make sure you’re pressing the power button instead of the reset button to power on the board.
Ha! That’s important! Yeah, I tried both.
Was the board in a chassis or were you using standoffs? Make sure there’s not something electrically conductive touching the board.
The board was in a chassis. As far as I could tell nothing was touching the board. The only thing in the chassis other than the board was all of the extra power supply cables.
Can you send information about the original (pop) power supply and a pic of the ATX connector/cable?
. This power supply turns on when connecting the green/black wires, but it’s old and I’m not certain that it’s fully functional.
