The White PC Engine, Black Core Grafx, and Gray Core Grafx II all have the same expansion port on the back so they are all compatible with the briefcase/IFU interface CD ROM unit. The White PC Engine expansion port will fit in the Super CD ROM unit but there is a very short cable on the left that connects the PC Engine to the Super CD ROM unit and I'm not sure if there is a corresponding plug on the White PC Engine unit. I'll look into it later but your best bet is to go with the briefcase.