5 Replies Latest reply on May 6, 2012 7:36 AM by Sleipnir

    DH61AG non existing COM port


      Hello guys,


      I recently build a new computer. I used these components:


      Intel DH61AG motherboard

      Intel i3 2100T CPU

      Intel 310 SSD 80 GB (mSATA)

      Intel 112BN WiFi mPCIe

      2x2 GB DDR3-1333 Samsung

      Coolermaster NA90 external PSU 19 Volts 90Watts

      Nofan CR-95C passive cooler

      Lian Li Q25A


      OS: Windows 7 64bit SP1 Home Premium


      Everything works fine... but when I look in the Device Manager, I see a "COM3" port, which simply does not exist.




      When I delete the COM-port, it's immediately found again by Win7.


      I updated the BIOS (recent version 0033), I did reset the DMI table (setting jumper to maintance mode an resetting the BIOS) and I replaced the mainboard with another DH61AG. I still see the COM3 port in the Device Manager.


      I find no option within the BIOS to deactivate any Legacy ports (COM, serial,...). As far as I know, the DH61AG has no internal connector for any COM-Ports.


      Can anyone confirm this bug or has anyone a solution?



      Torben from Germany

        • 1. Re: DH61AG non existing COM port

          Thank you for this report.  We are investigating the problem, since there definitely should not be any Comport listed for this board.

          • 2. Re: DH61AG non existing COM port



            I reinstalled Win7 yesterday... the COM-port is still existing (now it's called COM1 instead of COM3).


            I booted a Mint Linux 12 Live CD and checked the IRQ table plus lshw. There is no COM-port detected by Linux.


            Here are two more pictures taken from the Device Manager. As you can see, the "fake" COM-port even has got an IRQ asigned (IRQ 4). Also the COM-port is connected to the Intel LPC Controller.





            • 3. Re: DH61AG non existing COM port

              Hello guys,


              I flashed the new BIOS version (0037), but the COM-port is still existing. Will there be any solution by the next BIOS release?

              • 4. Re: DH61AG non existing COM port



                Yes, the plan is to roll the fix for this into the next production BIOS release.  However, I do not have an estimated release date for it yet.




                • 5. Re: DH61AG non existing COM port



                  I installed the new 0039 revision... the "ghost" serial port is still there When will Intel fix this bug?


                  Further I encountered a new bug after installing the 0039 BIOS: I use "low voltage" DDR3-SDRAM modules (I own 2x2GB Samsung and 2x2GB Crucial 1.35v memory kits). With revision 0037 and below, I was able to use my memory with 1.35v. Although the DH61AG was not able to detect the correct voltage, I could change the value manually within the BIOS. Directly after updating the BIOS to revision 0039, the DH61AG failed to boot. First I thought, the BIOS update process failed. But I recognised the power LED blinking as an error code referring to the memory. I could revive the DH61AG by changing the jumper to maintance mode and change the SDRAM voltage to 1.50v.

                  After some trial and error, I can say: When I change the voltage manually to 1.35v (which is the optimal voltage for low voltage RAM), the DH61AG fails to boot (with revision 0039). This sucks...


                  This is my 4th Intel mainboard (DH67CF, DG45FC, DG33TL). But this is my first Intel mainboard with such serious bugs.