HP Z800 How can I change the chassisnumber to the old chassisnumber in the BIOS

[HB_Gerd]

HP Z800 How can I change the chassisnumber to the old chassisnumber in the BIOS, if I changed the mainboard ?

I cannot change the UUID.

[SDH]

I have done this in the past on the Z workstations when I've upgraded from a version 1 to a version 2 motherboard.  Has worked for me each time.  Let me know if this does not work for you in which case I'll dig out my old notes to see if there is any difference from this vs what I did.  

You are right that you can't change the UUID, but this you can... LINK 

HP Business Desktops - How to Correct an Invalid Electronic Serial Number in BIOS | HP® Customer Sup...

This way your chassis serial number in BIOS will match what is on the outside of your case.

[HB_Gerd]

Hello SDH, thanx for your quick Answer. I´ll try it tomorrow, cause in Germany it´s time to do some different work, than to

play with the Z800. ;-))

[DGroves]

UUID is the combination of the Serial number and product ID and once set cannot be changed by the user

New replacement motherboards from HP will have the UUID empty so the tech/IT dept can enter the needed UUID

also as a side note, the UUID string is part of what MS license activation uses when registering a operating system

[SDH]

When I bought two Z620 v2 virgin sealed motherboards via very good luck on eBay I had to learn how to "brand", to "tattoo" them,  and their UUIDs were populated already.  This makes me think the UUID is firmware-burned at the factory and not something that a HP FSE could modify in the field.  There is no step in the branding process that allows one to enter a custom UUID, and from prior reading on this topic there are no duplicate UUIDs.  There are duplicate MAC addresses out there, however, but the likelihood of two identical ones on a single LAN is vanishingly rare.

[DGroves]

as i previously stated the uuid is created from the serial and product ID numbers

for current products (not EOL) Contact HP and give them your UUID and serial,

and tell them you replaced the board and need the matching SMC.Bin

you will also need  NbDmiFit-2.05 or newer (complete package) which allows Updating Hp Laptop and Desktop Machine Information such Serial number, SKU (Product  Number), CT number , Build Version and other things

https://www.finalfixer.com/2020/02/hp-dmi-tool-nbdmifit-wndmifit-all.html

[HB_Gerd · Accepted solution]

I tested it and it´s possible for me to change the chassisnumber, but this generates problems  during the boot on an ubuntu

testsystem, therefore I changed the chassisnumber back and took a pencil to overwrite the serial number on the label.

Thanx to the community for your advice.