I am trying to find out how to get the optional serial port adapter cable for the OptiPlex 3070 Micro.

https://www.dell.com/en-ca/work/shop/cty/pdp/spd/optiplex-3070-micro?view=configurations

I have tried Dell sales support they referred me to technical support. Neither of them seemed to have any idea what I was talking about. Which is odd since the cable is mentioned multiple places on the Dell website and in the service manual. If you follow the above link see #6 in the picture in the Ports & Slots section near the bottom of the page.

The serial port is actually present in the system it shows as COM1 (IRQ 0x04, I/O Range 0x3F8-0x3FF) in device manager and there is a place on the case to install the DB9 connector. All I need is the cable to go from the motherboard to a DB9.

Why don't I just use a USB to serial adapter? Well that was my original plan. I am using VirtualBox to virtualize an old 486 PC running QNX 2.21 which runs an piece of industrial equipment. QNX is pretty fussy about serial ports from what I have found. I have tried a couple different industrial grade USB to serial adapters without success, it does however appear to like(by like I mean QNX boots without error) the native COM1 port on the 3070. Unfortunately I cannot connect it to the machine to continue my testing without the aforementioned adapter cable. I have had similar experiences with USB to serial adapters in the past and I thought I was hedging my bets with this computer as I could always fall back to the native serial port.

I would be most grateful if someone could provide the part number for the serial adapter.

Thanks in advance.

Gary