Does the DELL PowerEdge XR12 support the StarTech PCIe card PEX4S232485?

I have questions about the PEX4S232485 (PCI Express card with 2xRS-232 and 2xRS-422/RS-485 ports) cards and whether they will work with the DELL PowerEdge XR12.

I have one XR12 with the VMware ESXi 7.0 hypervisor and another XR12 with the Linux OS.

For the ESXi system, if I install the PEX4S232485, will I be able to pass-through all/any of the 4 serial ports to a VM on this system, whether it’s Windows or Linux?

For Linux, are there suitable drivers for this PCIe card?

Does anyone have experience with this combination of products?

Hello and thank you for your interest in our Community.

I can confirm that this card will be compatible with Windows (Windows 2000 or Server 2003 and above) but unfortunately does not have any support for Linux. For Linux support, our only option for RS232/RS422/RS485 would be our USB version: ICUSB234854I.

As for how they would be handled over ESXi: you would need (for both our PCIe card or our USB adapter) to passthrough the device to the guest OS, which means all 4 ports would be handled by the same OS. If you are looking for a way to have 1 port per guest OS, you may rather consider 1 serial port per USB port, such as 4 x our ICUSB2324852 and individually passthrough one device per OS (or our ICUSB2321F if you don’t need RS422/RS485).

I hope this help! If you have any further questions, please let me know.

Emmanuel B.

Thanks for your quick response!

However, I have another couple of questions regarding this card:

For the RS-422 ports, are all the signals (TXD+, TXD-, RXD+, RXD-, RTS+, RTS-, CTS+, CTS-, GND) connected and used?

This card came with a CD with installation software and on the CD are two folders for Linux 2.4 and Linux 2.6 and it seems to contain software for using the card with Linux. Now I see that the documentation says that only Windows is supported but presumably this means that it is possible to install this card and use it with a Linux system albeit in an “unsupported” state. Would that be correct?


For the RS422 (and RS485) only the Pins 1 to 5 are connected (TXD+, TXD-, RXD+, RXD-, GND). The information for the pinout (and the jumper settings) can be found in our Instruction Manual.

As for Linux, it is due to the chipset having past support but not having support for current LTS versions of Linux. For this reason, we had to also officially drop support for Linux on this card. In order to avoid misunderstanding, we will be updating the material relative to this card in order to better reflect this.

I hope this help, and I apologize for the inconvenience. If you have any further questions, please let me know.

Emmanuel B.

Has anything changed since March? I’m sure many users want Linux support.


I am quite sorry, but this has not changed. The chipset itself does not have support for modern versions of Linux so this isn’t something we can officially support or add. I do apologize for the inconvenience. You can always research the specific chipset (SystemBase - SB16C1052PCI) in Support forums for your Linux distribution’s community as someone may have tried and perhaps succeeded.

I hope this help, and I apologize for the inconvenience. If you have any further questions, please let me know.

Emmanuel B.