Hmm just a quick search shows nothing above XP as you said. The dev ID I209 does not even show on this 2006 archive:
http://web.archive.org/web/20060823011452/htt … b/cs-012904.htm (so was never used on standalone adapter afaik).
from datasheet: "Full pin compatibility with the 82559 and 82559ER controllers and
— Backward compatible software to 82559ER controllers" ok so the proper driver is backward to 82559ER ???
added: Also noted that there is updates from 2002 thru Nov 2008 in the datasheet which takes it past the start of Win Vista....
what motherboard is this on ?

added 2: found reference to XP64 and Vist64 and Win2003 server 64bit here: http://web.archive.org/web/20070208214548/htt … x?ProductID=994
and this but no Vista listed??
https://web.archive.org/web/20060322051702/ht … ating%20Systems
sorry do not have time to dig deeper right now, have a family thing have to get going on...

Thanks for the info. Unfortunately archived pages like these aren't going to be too helpful. Someone has to dig into the Internet Archive library instead of the wayback machine to look for it... However, so far I haven't found anything new there.

For NT 3.51, modding the driver binary to look for 1209h instead of 1229h would allow the onboard adapter be picked up by the driver (at least I could see the I/O space, IRQ, and MAC address). However, it seems the driver code path is not fully compatible as the adapter still cannot be started. I still have a long, long way to go to figure out how Intel's network drivers work as they appear very complicated under the hood -- aside from device IDs, there are different code paths for different revisions as well as subsystem IDs.

From what I found, the ER variants (82551ER/82559ER) lack a few SMB-related pins but otherwise fully pin and footprint compatible with vanilla 82559. Not sure how this would make the ER variant's code path deviate from the vanilla.

The board in question is AIMB-865. For those with 100Mbit ethernet 82551ER is used, though there were some variants with Gigabit ethernet. I think 8255xER is also used by some other period-correct motherboards mainly for embedded purposes, as there were even drivers for WinCE and XP Embedded according to some driver sites.

Don't know whether replacing the 82551ER with a vanila 82559 would continue to work on such boards... I don't have the right tools to handle BGA components yet, though it might be interesting to conduct such experiments when possible...

Did not find any NT 3.51 drivers for a 82551/59 just NT 4.0 and up on a quick search.
Some of us have had good success digging into wayback, I was able to get many of the Intel motherboards goodies after Intel removed them. Same is possible with most of the Network stuff.
Yes saw that particular ether chip was used on some SBC and considered an OEM part whose drivers would have been on the long gone Intel ftp. The Intel ftp at archive lib does not have all the drivers that it should have contained back in 2014.
Maybe PC Hoarder will see this and go digging, he is very good at it.

Horun wrote on 2024-02-18, 02:05:

Did not find any NT 3.51 drivers for a 82551/59 just NT 4.0 and up on a quick search. Some of us have had good success digging […]
Show full quote

Did not find any NT 3.51 drivers for a 82551/59 just NT 4.0 and up on a quick search.
Some of us have had good success digging into wayback, I was able to get many of the Intel motherboards goodies after Intel removed them. Same is possible with most of the Network stuff.
Yes saw that particular ether chip was used on some SBC and considered an OEM part whose drivers would have been on the long gone Intel ftp. The Intel ftp at archive lib does not have all the drivers that it should have contained back in 2014.
Maybe PC Hoarder will see this and go digging, he is very good at it.

Vanilla 8255x (E100B) has NT 3.51 (NDIS3) drivers. I haven't found NDIS3 drivers for 8255xER (E100E). Not sure if it ever exists.

Thanks for the hint on Intel FTP archive. Will try getting it and take a look inside. 2014 should be enough for any up to Win7 (x64) stuffs but I wonder how old the FTP would reach.

So far there's no way to actually change PCI device ID for 82551ER via EEPROM word 23h, even though the word in question is programmed to 1209h in the reference EEPROM map. The ability to change PCI device ID was something specific to 82551QM which already used 1229h and thus could already be picked up by most of the drivers...

EDIT: Turned out that archive is unlikely to be helpful...

This is not the "download" you are looking for.... this does not include drivers for your beloved motherboards, Chipsets, LAN, Audio, ... this is PDF files, and PR stuff about motherboards, other products etc and other B.S. Don't waste your time downloading the 70GB file... it does have a few files but mostly 97 percent worthless. Intel must not have kept the "good Stuff" on the FTP side.

EDIT 2: I ended up plugging a RTL8139C based network card to that system. Now the system has working network across all OSes. Sadly the board doesn't have the ability to disable the onboard adapter.

Well that was my next suggestion (add a diff NIC), Hmm you would think bios would have a choice for the onboard. I did look at the bios you posted in other topic, both are dated 2024 at end if you HEX them and are AMI.
Are they really that new ? Did you ever find x64 drivers for the 82551er
Also looked at some SBC that has same 82551er (EMAC Inc PCM-3353, PCM-3372, etc) and have no drivers different than you found already.
Also looked at MSI K7D which does have a 1209 ID inside it's lan driver (w9x-2k) and stumbled on some file called Intel-FORCED-5x86-OLD-drp.zip also has ID 1209 listed (has shit load of drivers, Attached.).
Found a few others too but do not think NT3.5x will ever work with it, there is a diff in how NT 3.5x and NT4 work with parts...and maybe the chip was never designed for backward compatibility (there is a few Realtek like that)
Am thinking the 82551er is sort of a bastard chip that Intel pawned off to OEM's for cheap and is why very few boards actually use it., then changed to 82559er when issues developed...
odd the resources talk about 2002 thru 2008 but yet no forward/backward OS support.

Horun wrote on 2024-02-19, 04:05:

Well that was my next suggestion (add a diff NIC), Hmm you would think bios would have a choice for the onboard. I did look at the bios you posted in other topic, both are dated 2024 at end if you HEX them and are AMI.
Are they really that new ?

No. Those BIOS themselves are still old. I dumped and updated/added microcodes that's all.

I'd like to dive deeper into modding the BIOS to fix some issues that I already know how to fix after boot, just I don't know which tool I actually need (neither AMIBCP nor MMTool). It's off-topic for this thread, as I've already brought up a topic about that question a while ago...

Horun wrote on 2024-02-19, 04:05:

Did you ever find x64 drivers for the 82551er Also looked at some SBC that has same 82551er (EMAC Inc PCM-3353, PCM-3372, etc) […]
Show full quote

Did you ever find x64 drivers for the 82551er
Also looked at some SBC that has same 82551er (EMAC Inc PCM-3353, PCM-3372, etc) and have no drivers different than you found already.
Also looked at MSI K7D which does have a 1209 ID inside it's lan driver (w9x-2k) and stumbled on some file called Intel-FORCED-5x86-OLD-drp.zip also has ID 1209 listed (has shit load of drivers, Attached.).
Found a few others too but do not think NT3.5x will ever work with it, there is a diff in how NT 3.5x and NT4 work with parts...and maybe the chip was never designed for backward compatibility (there is a few Realtek like that)
Am thinking the 82551er is sort of a bastard chip that Intel pawned off to OEM's for cheap and is why very few boards actually use it., then changed to 82559er when issues developed...
odd the resources talk about 2002 thru 2008 but yet no forward/backward OS support.

No I haven't. It seems Intel never really released anything past that for 1209h. Only 1229h has x64 drivers. 82551QM is the one that uses 1229h (changeable), whereas 82551ER/IT uses a hardcoded 1209h.

NT 3.51 uses NDIS3, while NT4 uses NDIS4. I'm still exploring how to get more information out of driver binaries... so perhaps I'll compare E100ENT that I found with a similarly dated E100BNT (both NDIS4) in hope I could find some hints on behavioral differences between the two Device IDs/models...