If it makes any difference, certain models might have different bootagent versions, I have no idea. I seen a screenshot of an intel bootagent I think the version was 2.20.0 or something, it was higher version over my version.
But, the model number on the unit alone is
As the question remains, am I using the latest bootagent for my PWLA8391GTBLK?
The latest Gigabit Ethernet PXE Boot version for Intel(R) Boot Agent is 1.4.04. The latest UEFI version is 3.5.15. The UEFI driver has not changed recently.
See the "Boot Images & Drivers" section of http://www.intel.com/support/network/sb/CS-023752.htm for recent version numbers.