If you have a parallel device (such as a printer), connect it to the parallel connector (4).
1 Serial Port 1 Connector
1a Serial Port 1 Front Connector (RJ48)
2 Serial Port 2 Connector
3 Serial Port 3 Connector
4 Parallel Connector
32 Eserver
pSeries 630 Model 6C4 and Model 6E4 Installation Guide