Second Serial Port on HP d330 ut P4 system

[IBM_User]

Since this system has onboard graphic there is only one serial port installed on the motherboard.
While cleaning the system I expected to find a header for an second serial port, well there is one
labeled Serial B.

Unfortunately, there is no entry in the BIOS for the second serial port, because of this,
can any one tell me how I get it activated?

It's a HP Compaq (Compaq is the model not the brand) d330 ut, and seems to be from around 2003.

 

[IBM_User]

Solved!

Pin 10 of the "Serial B" header must be tied to ground to get the COM2 activated.

 

[electricelectric2021]

and pin 12 on other systems ?

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