IBM B50 - Manual (Page 25)

B1 Battery connector
J1 Not used
J2 5x5 Auxiliary 5v connector
J3 Audio input connector
J4 Internal SCSI connector #2
J5 CD-ROM audio connector
J6 CD-ROM audio connector
J7 Power connector
J8 Power connector
J9 Not used
J10 Media Fan connector
J11 Memory Connector 1
J12 Not used
J13 Audio output connector
J14 Not used
J15 Remote Power-up Jumper
J16 Diskette drive connector
J17 Microphone jack
J18 Reset Connector
J19 Memory Connector 3
J20 Power-on password jumper
J22 Headphone jack
J23 Serial port connector 2
J24 Serial port connector 1
J25 Tablet port connector
J26 CPU fansink connector
J27 System fan connector
J28 Memory Connector 2
J29 Not used
J30 System fan connector
J31 Not used
J32 Privileged-access password
jumper
J33 Internal SCSI 16-bit connector
J35 SCSI security jumper
J36 SCSI security jumper
J38 External SCSI connector
J39 Riser card connector
J40 Power Switch connector
J41 Op Panel Connector
J42 Power Indicator LED connector
J43 Hard-disk activity LED connector
J44 Voltage Regulator connector
J45 Ethernet twisted pair connector
J46 Internal Speaker connector
J49 Parallel port connector
J50 Ethernet AUI
J53 Ethernet EPROM connector
J56 Mouse port connector
J59 Keyboard port connector
J139 Memory Connector 4
Chapter 1. Reference Information 1-7