I'm losing my mind. This old graphics tablet connects to the PS/2 port on an old PC for power. There's a separate serial cable for the actual data connection. I want to supply it power without needing to connect it to a PS/2 port, so an adapter for USB would be ideal.

I know others have achieved this but I can't find the details. Can anyone help? The search results are full of Playstations because it misinterprets the "PS/2" part.