Black screen. SSH in, look at dmesg, find this:
[113524.995794] NVRM: Xid (PCI:0000:07:00): 79, pid='', name=, GPU has fallen off the bus.
[113524.995798] NVRM: GPU 0000:07:00.0: GPU has fallen off the bus.
Black screen. SSH in, look at dmesg, find this:
[113524.995794] NVRM: Xid (PCI:0000:07:00): 79, pid='', name=, GPU has fallen off the bus.
[113524.995798] NVRM: GPU 0000:07:00.0: GPU has fallen off the bus.
Just in case:
This means a problem with PCIe bus connection. Reseat the unruly card. If problem persists, check for cracks near your PCIe connector.
It might also be an (unlikely) problem with motherboard especially if you scratched it or CPU if you bent some pins.
Could it be a power issue too?
Yes, you are right that is a possibility.
I remember that actually I encountered it once with a power supply problem, but it appeared along with other random issues, like restarts, application crashes, and nvidia-smi not responding.