Moxa CP-104EL 4-port PCI-E serial card

This came with a 4-port DB25 lead as standard. 4-port DB9 lead also included.

Low and standard profile brackets included.

We have a couple of the 8-port versions of this card in a PC working as a Linux console server for out-of-band management for networking equipment. In this application use standard Cisco console cables and connect them to the DB9 lead. This also works for Mikrotik equipment with RJ45 console. If it has DB9 console use a null modem cable.

This is an industrial spec card not a low cost one. See here

$190 + Courierpost.