Recently, I’m busy backing up my laptop and recovering the system via network. I tried to adjust the “Jumbo Frames” option for network performance gain, but accidentally found that Intel Pro/1000 PL Network Connection, built-in the ThinkPad 6-series laptop, didn’t support such functionality.
In my desktop PC, the “Jumbo Frames” option can be changed through MMC property page:
The Intel webpage says that the PRO/1000 PL does support Jumbo Frames, as shown below:
But I couldn’t find the option to adjust the frame size in my laptop, even after I installed the latest Intel driver including the PROSet:
Finally, I found the answer in the Spec. update of Intel 82573 Family Ethernet Controller. Due to design flaw of the Intel 82573 Family (including 82573E/V/L), the 82573E/V version does not support Jumbo Frames at all. And the 82573L chip only supports jumbo frame when the ASPM (Active State Power Management) is disabled. The only workaround to get jumbo frame is to modify the EEPROM to disable ASPM. See below.
This is a pretty huge screw up from both Intel, and Lenovo for having these cards in their notebooks. I would actually be interested in flashing the EEPROM if someone had one out there that was known to work.