P17 and J4 are located on the optional COM port card
QuickSpecs
HP rp5700 Long Lifecycle Desktop PC
HP rp5700 Long Lifecycle Desktop PCHP rp5700 Long Lifecycle Desktop PC
HP rp5700 Long Lifecycle Desktop PC
Technical Specifications - Communications
DA - 12758 North America — Version 26 — March 22, 2011
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