How to change MAC address in the BIOS for onboard NIC....

[BaDaBooM]

Here's the deal: I have multiple computers using the ECS K7S5A motherboard. I went to deploy them using RIS and at first had a problem with the ECS's lame Pre-boot rom for the onboard NIC not working with RIS. So I did a little research and found out how to replace that module with a PXE-compliant module using AMIBCP.exe. I tried it out and got one working and thought great!

Not so fast though.... when I tried to install the next one, I got the duplicate GUID message in RIS setup. From what I understand the GUID it uses is based on the MAC address of the network card. (Confirmation on that is welcome) So I need to figure out a way to change the MAC address by editing the BIOS? Anybody know how to do this or if I'm going in the wrong direction? Also remember this is before the OS is loaded so I can't just change it in the OS under the driver properties. Thx.

 

[jaeger66]

Originally posted by: BaDaBooM
Here's the deal: I have multiple computers using the ECS K7S5A motherboard. I went to deploy them using RIS and at first had a problem with the ECS's lame Pre-boot rom for the onboard NIC not working with RIS. So I did a little research and found out how to replace that module with a PXE-compliant module using AMIBCP.exe. I tried it out and got one working and thought great!

Not so fast though.... when I tried to install the next one, I got the duplicate GUID message in RIS setup. From what I understand the GUID it uses is based on the MAC address of the network card. (Confirmation on that is welcome) So I need to figure out a way to change the MAC address by editing the BIOS? Anybody know how to do this or if I'm going in the wrong direction? Also remember this is before the OS is loaded so I can't just change it in the OS under the driver properties. Thx.

I don't think that's the issue. The MAC addresses are already different so even if you could, changing them won't help.

 

[BaDaBooM]

Nope, actually the MAC address are exactly the same in this case. I think since this is an onboard NIC, that the MAC address is determined in the BIOS (i.e. the NIC rom module). So when I took out the non-RIS-compatible module and put in my PXE-compliant one for each computer, each one got the exact same MAC address since I didn't even consider editing the module itself. However there must be a way to edit this. Calling all elite hardware tweakers.

 

[paralazarguer]

Nope, actually the MAC address are exactly the same in this case.

They're not supposed to do that. How could you set up a network of ECS K7S5a boards if they all had the same mac adress? Answer: you couldn't.
They can't be the same.

 

[Boogak]

Originally posted by: paralazarguer

Nope, actually the MAC address are exactly the same in this case.

They're not supposed to do that. How could you set up a network of ECS K7S5a boards if they all had the same mac adress? Answer: you couldn't.
They can't be the same.

That's what I'm thinking. I thought it was guaranteed that every network card (onboard or not) was guaranteed a unique MAC address??

 

[jaeger66]

Originally posted by: paralazarguer


They're not supposed to do that. How could you set up a network of ECS K7S5a boards if they all had the same mac adress? Answer: you couldn't.
They can't be the same.

Yeah, what he/we said.

 

[BaDaBooM]

Originally posted by: paralazarguer

Nope, actually the MAC address are exactly the same in this case.

They're not supposed to do that. How could you set up a network of ECS K7S5a boards if they all had the same mac adress? Answer: you couldn't.
They can't be the same.

Ok, sorry if I wasn't clear. I'll explain better. I'm sure that when they shipped me the board, none of them had the same MAC address. A little history on the K7S5A: between shipping versions of the motherboard, they kept switching between an PXE module and another module for their onboard NIC. I unfortunately got the non-PXE version of the boards which isn't compatible with RIS. So I downloaded the PXE module, then used AMIBCP.exe to remove the non-PXE module from the BIOS and replace it with the PXE module. Since I used the same file (that I downloaded) without editing the module's MAC address (I guess that is where it stores it cuz that was the only thing I changed), now all of my boards have the exact same MAC address - admittedly by my own doing. I have confirmed with my own eyes that they do have the same MACs now. However I'm sure it's just a matter of getting the right program to edit the PXE module. I looked through all the options of AMIBCP.exe but I didn't see any way to edit individual modules. I guess I just need some type of editor where I can look for the MAC address and change it for each computer then re-flash.

 

[BaDaBooM]

Originally posted by: Boogak

Originally posted by: paralazarguer

Nope, actually the MAC address are exactly the same in this case.

They're not supposed to do that. How could you set up a network of ECS K7S5a boards if they all had the same mac adress? Answer: you couldn't.
They can't be the same.

That's what I'm thinking. I thought it was guaranteed that every network card (onboard or not) was guaranteed a unique MAC address??

BTW, it is possible that you can get duplicate MACs (not from editing like above), though extremely unlikely. I had it happen to me once while I was working at a very large company (125,000 employees). It was a b1tch to troubleshoot because up until then I thought they had to be unique also. They are not exactly guaranteed to be unique, just very well spaced out. Since most companies don't have THAT many computers on the same network and MACs are not important unless you are on the same LAN/WAN, they only try to keep the same LAN/WAN from getting the same MACs. The MAC ids are divided by area of the globe and manufacturers ship duplicate groups to different sides of the world which makes it very unlikely to get duplicate MAC address on the same LAN/WAN. Just an FYI - unrelated to my problem.

 

[Adul]

well you can try using a hexeditor

 

[Lord Evermore]

The MAC address is encoded in the Ethernet controller (which is integrated in the chipset), not in the BIOS.

Wait, no I'm probably wrong. But changing an external chip wouldn't suddenly make the MAC address change in the BIOS, and the MAC address is based on the Ethernet controller vendor's ID.

 

[BaDaBooM]

Originally posted by: Adul
well you can try using a hexeditor

Ok, I had that thought but since I have never dove into hexeditors I wasn't sure if that was the right tool to use. I only understand the general idea of editing hex (I know, editing hexidecimal), but not sure if there is more to it than that. Is there one you would suggest for a hex-newb? I suppose I could use a search function to find the MAC and change it.

Edit: well, I downloaded a freeware hexeditor and played around with it. I used the search function, but it didn't find the MAC address in the PXE module or the whole BIOS.... so now I'm a bit confused.

 

[BaDaBooM]

Originally posted by: Lord Evermore
The MAC address is encoded in the Ethernet controller (which is integrated in the chipset), not in the BIOS.

Wait, no I'm probably wrong. But changing an external chip wouldn't suddenly make the MAC address change in the BIOS, and the MAC address is based on the Ethernet controller vendor's ID.

Right, vendor's ID is a part of it... I would just change the last digit or something. Also when I say replacing the module, I don't mean an actual chip. I'm just talking about editing the firmware using AMIBCP.exe - it's a BIOS editor. And when I did that it did change the MAC (to my surprise). It may just be unique to onboard NICs or even just this implementation of an onboard NIC.

 

[Lord Evermore]

AHHHH. Okay. Then yes it probably wrote a new MAC from whatever default it had. Or it may not have written any MAC and assigned them all zeroes. Were you able to see what GUID was being duplicated (and then figure out what the MAC it was based on is)? ECS's BIOS updates occasionally mentioned losing the MAC address with some of them, so it may not even be the updating of the module's fault. Of course, if simply fixing the BIOS allows them to make the MAC reappear, then it may not be somewhere that it can be overwritten, but rather hard coded and simply inaccessible.

You might try flashing the BIOS back to an original, so you can get the existing MAC address and then figure out how to restore it after the module change.

 

[BaDaBooM]

After getting some sleep and thinking about it, I am confused now. People flash the BIOS all the time, but it doesn't change their onboard NIC's MAC address. Unless when they flash it, the rom doesn't change that specific module. I dunno.

I searched the module with a hex editor and I did come up with "MAC Address" and "GUID" in a text search. However the data that followed didn't seem to be either of those things. Just a coupld of 00 00 and then 0C 0D which makes me believe that those might just be where it stores the text it displays on the screen while it's doing a network boot.

Also I check out their web page and I am using the latest BIOS with no mention of loosing MACs. I can reflash it with the original but then I am stuck again trying to figure out how where the MAC is stored when I go to put the module back on.

Hmmm......

 

[Lord Evermore]

Reflash the BIOS then look at it with a hex editor. I think the issue may be that when you change the module, the BIOS no longer is able to locate the hard-coded MAC address, which is still there and not overwritten.

 

[Budman]

go to ECS site,there a little util there where you can put any mac adress you like.

Once when I had this board I flashed the new bios & lost my nic MAC adress, I had to use this little util & it works fine.

Edit, found the Util.

http://www.ecsusa.com/downloads/bios/k7s5a_id.exe

If you lost the LAN ID after flash BIOS and clear CMOS, please download this utility file to repair it.

BTW your mac adress is on your install CD and on the Mobo's printer port,it's a sticker.

 

[BaDaBooM]

Thanks Budman, worked like a charm! Took me a little while to post cuz of other pressing issues. Funny how everyone's focus can suddenly change from one project to something else when stuff breaks.