The plug side that goes into the PSU is not standard.
The PSU is an EVGA 1600 G2 supernova.
How do I plug this in? I can’t find a compatible cable or plug adapter.
Appliance connectors: https://en.wikipedia.org/wiki/IEC_60320
North American connectors: https://en.wikipedia.org/wiki/NEMA_connector
Worldwide industrial connectors: https://en.wikipedia.org/wiki/IEC_60309
Worldwide standard connectors: https://en.wikipedia.org/wiki/AC_power_plugs_and_sockets