NEC PC Engine collectors, can feel confused by the various system cards and game types.

NEC released cards to boost the systems’ memory capacity. Each card corresponds to a set of NEC consoles.

There are two different System console upgrade cards for NEC consoles;

The Super System Card 3.0 can be bought separately, or be found built into either the Super-CD-Rom² (CD peripheral)  or the later NEC Duo consoles.

These cards are used to run any games with a Super CD-ROM² format.  

Similar to HuCards, a system card can only be used in the region it was meant for.

The cards sold on RETROPIXL are only valid with Japanese versions of the consoles.

In terms of games, it is possible to tell what format a game is simply by looking at the front of its manual or box.