A50p

Types: 8128, 8185, 8186, 8187, 8188, 8189, 8190, 8192, 8193, 8194, 8195, 8196, 8197, 8413, 8414, 8415, 8430, 8431, 8432, 8433

Standard Features

 * Intel Pentium 4 Processor (some models)
 * Intel Pentium 4 HT Processor (some models)
 * AC’97 with ADI 1981B Audio Codec
 * 25-pin, Extended Capabilities Port (ECP)/Extended Parallel Port (EPP)


 * 9-pin serial connector


 * Eight 4-pin, USB connectors (two on front panel and six on rear panel)


 * PS/2® mouse connector


 * PS/2 keyboard connector


 * Ethernet connector


 * VGA monitor connector


 * Three audio connectors (line in, line out, and microphone)


 * Front connectors for microphone and headphone (some models)

Original OS

 * Windows XP Professional
 * Windows XP Home Edition
 * Windows 2000 Professional (until 2005)

Source:
http://ibmfiles.com/ibmfiles/thinkcentre/a50p_usersguide.pdf