Supermicro AOC-MTG-i2T User Manual page 27

Remove the following lines from the /usr/src/sys/conf/files.i386 file, if they exist:
/dev/ixgb/if_ixgb_fx_hw.c optional ixgb
/dev/ixgb/if_ixgb_phy.c optional ixgb
Edit the kernel configuration file (i.e., GENERIC or MYKERNEL) in /usr/src/sys/
i386/conf, and ensure the following line is present:
device ixgb
Compile and install the kernel. Reboot the system for the kernel updates to
take affect.
3-9
Chapter 3: Installation