Z800 Z820 Firmware revisions

[SDH]

Was just checking on eBay... sometimes a seller shows the sys info page. Note that the AMT controller has "higher" value rather than lower on this one, and another I saw there. I double checked my Z620 here and what I said in my post just above is confirmed as correct. So, maybe the higher vs lower does not help so much... Here are 2 pics from US eBay... top is older v1 and bottom is newer v2.

[r1_rn22]

Thank you very much for your support. As again. I really enjoy this technical discussion, as it might also help others with a similiar problem, to at least create a working board again:

I inspected the BIOS file that I read out, please see the following (referring to the document you shared, some of the hex addresses are messed up with nonsense. I got the feeling, that the update in Win10 corrupted everything, but saved some informations):

The lower MAC (without AMT) I could fill in using the CTRL-A and edit the informations:

For this part of the UUID, I have no idea what it is and where it can be found. I will later unsolder the BIOS chip again, and do a readout. As I now filled in the MAC, and it wont be a place listed below, I can for sure identify the place where it is:

Things like MAC addresses and serial numbers are also stored in the BIOS flash in specific places:
• MAC addresses: “0x001000,0x002000,0x03470C, 0x03B84C AND 0x03B985”
• [Personal Information Removed]

From the original BIOS readout file:

It seems like this part was spared out in the update process / as the document also describes. But it contains FF now, as the new BIOS file was not modified, it was just put on the flash chip and thats it. But it will help me identify what goes where. See, the next part is the meshed up area:

In the good new / stock BIOS file it is all empty space with "FF".

What I will do now is: Unsolder the flash chip, read it, fill in the MAC at the given areas from the document, and see if it works. I hope the AMT MAC will also appear then, as its the higher last digit.

The boot block itself also looks damaged ... first the original one, then my corrupted one:

Also, the signature is mixed:

I believe the process in Win10 mixed up everything, and there are some incompatibility issues. As soon as I have the new BIOS chip readout, I will check it versus the document you provided and see about the MAC addresses and the UUID then.

As by now everything is 3.96 (also the bootloader and all other parts of the image), a hw version 1.00 board can boot with the latest firmware image, even in case of a damaged chip.

[r1_rn22]

I'm a big step ahead, I could dump the BIOS without unsoldering the chip. The manually added MAC showed up at 4 locations:

2EB5C, 2EC96: after the first appearance, the manually added serial number of the case shows at: 2EC4A

3068C, 307C6: after the first appearance, the manually added serial number of the case shows at: 3077A

So, I guess one is the used one, the other one looks like a backup of previous values or a default.

The manually added MAC with the 4D at the end I added to the UUID shows at:

2FC36

3246C

325A6

After combining, the UUID is at location 26E73 and is also at 26FAA and 2EB53 and 2EC8A and 2FAF6 and 2FC2A and 30683 and 307BA and and 32463 and 3259A

MSB/LSB is swapped in some parts of the UUID. So, the UUID is present at the locations 2FC2A, 32463 and 3259A.

The last digits of the UUID are at 2FC36, 3246C and 325A6

Locations 2EB53, 2EC8B 30683 307BA also had the first parts of the UUID before.

Locations 1000 and 2000 are FF'ed - clear to me. I need to add it there manually. I will now try to conclude the appearance of the UUID in combination to the MAC, although I know the last part of the UUID is not the MAC. It can also be a random part, which I will verify as well.

[r1_rn22]

Found it. I modified the UUID from FC to FE at the end, so I can identify the locations of the MAC and the UUID.

The lower active MAC with FC at the end is at the following locations:

2EB5C (with the UUID minus the last block of UUID before)

2EC96 (with the UUID minus the last block of UUID before)

3068C (with the UUID minus the last block of UUID before)

307C6 (with the UUID minus the last block of UUID before)

The previously active UUID with MAC with FD at the end is at the following locations: Means, this is the old UUID:

2FC36

3246C

325A6

The active UUID + the active last part that was changed to FE is at:

3289C

329D6

So, there is a shadow storage for old values in the BIOS at the given areas. And, the manually added MAC is always combined with the front parts of the UUID:

Please note, its MSB LSB swapped. The above is like that in the BIOS file at all mentioned locations:

After this block, either the entered value of UUID shows at the presented locations, or the MAC address.

I will now manually add the old BIOS regions to try to get the old UUID, if possible. The old AMT MAC is the higher one, so this is cleared out already and also listed in the old part of the BIOS file that I could read from the old chip.

I'm curious if its possible to do the flash of the whole file from the DOS shell. Is there any jumper to consider, like system block protection? The manual gives no indication about that.

[r1_rn22]

Success. The 2nd NIC is working again, I could add the MAC by using FPT.EXE with -L 16384 on the modified working BIOS file that I read out before.

The only thing that now is missing is the correct prvious UUID, which won't be restored, as the original flash regions are filled with corrupt data.

But flashing of segments of the BIOS file is also working. So, the issue can be closed.

If needed, I can help or explain the process for further reference.

[r1_rn22]

Also, Win10 was marked as "not activated" - now its "activated" again, same with the Office suite.

[SDH]

Well, that is great news! That would imply that your UUID is now correct. I'm glad you understand all this.

I've been described as an idiot savant by my close friends... more an idiot than a savant, but I'll take it. You are more the savant.

Here's a link that might help:

Solved: Crisis Recovery Jumper Z620 Z420 Z820 Revealed - HP Support Community - 6658619