• ×
    Need Windows 11 help?
    Check documents on compatibility, FAQs, upgrade information and available fixes.Windows 11 Support Center.
  • post a message
  • ×
    Need Windows 11 help?
    Check documents on compatibility, FAQs, upgrade information and available fixes.Windows 11 Support Center.
  • post a message
The HP Community is where owners of HP products, like you, volunteer to help each other find solutions.
HP Recommended
HP Z820

Hello there, since I want to upgrade my hp z820 workstation to ivy bridge v2 Xeons, that has a buildin Rev1.00 mainboard with an incompatible bootblock date, I'm playing with the idea to invest in a new Rev1.03 mainboard with the correct bootblock date. The problem is, how can I setup the blank serial and product number in the bios? Any kind of help is always welcome!


Accepted Solutions
HP Recommended
HP Recommended

Do you already own the replacement v2 motherboard?  If so please post a pic of the small white barcode label on the motherboard that gives part numbers to the left and right.  That way I can confirm for you that you indeed have a version 2 motherboard with the later boot block date.  Don't rely on the "Rev" number.


If you buy a used motherboard for this ZX20 family of workstations it will have already undergone a process termed "to brand" or "to tattoo", and critical codes that are available on labels on the source workstation's case will have been firmware-burned into BIOS at the factory.  That "branding" process is a 1-time event.  There is one entry in the branding process, however, that can be changed at will, which is the Chassis Serial Number.  I can let you know how to change it if you need that (see my added post below for details).


If the v2 source workstation was licensed (and branded) for Linux rather than W7Pro64 you would not be able to do a self-activating clean install from a HP W6Pro64 Recovery Disc set.   There is usually no label that tells you what it was originally branded for... luck of the draw generally but the OP shows a motherboard with a label that let me know it was branded for Linux rather than for Windows 7/8. 


However, you can do a clean install and feed the activation process the single on-sticker HP COA serial number (usually found on the top of the case) to activate it.  You cannot clone that type of install to another W7Pro64 same-type workstation.  You can if your build is from the proper Recovery Disc set and the workstations involved are properly branded.


In contrast, if you buy a new "virgin" motherboard that has not been branded then you get to enter the codes from your original case stickers and you can essentially clone the entries that worked on your v1 motherboard over to the v2 motherboard and set its OS to W7Pro64 assuming you had a W7Pro64 v1 motherboard to start with.


That process is complex, tricky, and I have done it.  I specifically used the codes from my original v1 Z620 to brand a virgin v2 Z620 motherboard, and that is now happy to use the HP W7Pro64 Recovery Disc set to do clean installs from.  It was a big project.  I do not know if you can change the UUID of the virgin motherboard from what it comes with.... I left it at that rather than take the risk and try to match it to the UUID of my original v1 motherboard.


In contrast, It is easier to buy a used v2 motherboard and hope you get a W7Pro64 branded version so you install a HP version of that OS from a HP Recovery Disc set.  Then you can upgrade the W7Pro64 install for free (still) to W10Pro64.  The W10 activation process harvests the UUID from the motherboard and registers that on the central MS W10 activation servers so that in the future you can do clean W10 installs on that motherboard easily and the build will activate by just checking in with MS.  Of interest, an image of this W10 build can be cloned onto another same-type workstation if that has been previously W10Pro64 activated.  Statistically there is only 1 UUID for each workstation in the universe.  Not so for MAC addresses.


Regarding flashing a v1 motherboard over to a v2 that SalSimp has accomplished.... that is a technical feat of genius, and does risk loss of the v1 motherboard in the process.  My work on the branding process was elementary in comparison.  I can swap in a v2 used motherboard in roughly 1/2 hour.... so for me that is the easiest, fastest and safest way to go.

HP Recommended



Hello there,

thank you very much for your fast reply, I did not buy the new board yet, but these are the stickers on the new mainboard (from the seller).


Where exactly do I have insert the serial and product number and how? Is there a special software needed? Where do I find the Chassis Serial Number? I have a sticker at the top of my z820 with Product No. LJXXXXX and Serial No CZCXXXXXXX (X are variations of numbers and capitals). Is this the correct information?


HP Recommended

First off, I'd buy that board now assuming it is a fair price in your mind.  It is a late v2.


Second.... the smaller square label in the second pic..... 708610-001.... that is a HP "Spares P/N" that also shows up on the left on the associated bar code label.  That is a big hint that this is a Linux version motherboard.  If it was a Windows branded version motherboard then that smaller square label number would have been 708610-601. 


The term "No DPK" means no Digital Product Key has been branded into the firmware of the motherboard that would allow the HP OEM Windows activation process see inside BIOS that the hardware was properly licensed to use the HP OEM COA self-activating Recovery Disc set.  That bottom number on the left ending in -601 next to "W8 Pro" would have been the recommended Spares P/N on the smaller label otherwise.  MS gets a fee in one case and not in the other. 


You cannot change the branding after it has been done the first time, so no you cannot brand in W7/W8 licensing after the fact.  All our Z620s that came with a "W8 Pro" DPK designation can also run old and new W7Pro64 Recovery Disc sets from both the v1 and v2 time frames.  The newer ones are better kits.  W10 finally is becoming the best way to go for us.


It is rare that you'll have that little square label that lets you deduce the motherboard's branding based on the stated replacement motherboard's Spares P/N from that sticker.


The Assembly P/N ending with -004 on the right side of the bar code label shows it is v2 motherboard for sure (if that ends with -003 or -004 you can be sure).  Do not rely on the PCB Rev number...  I've found 1.02 printed on v2 motherboards and also on v1 motherboards.


OK.... below is much more than you wanted to know but this is a copy/paste from our forum friend Skylarking with some of my past additions.  The Chassis Serial Number usually starts with something like 2UA......    You can change that to whatever you want as many times as you want but only by access via the CTRL + A method described below.  Some of the other things you can change from the surface level of BIOS.  Others you cannot ever change after the motherboard has been branded initially.  Here you go:






Skylarking Method to Modify Motherboard ID Info via F10 > Ctrl + A

(2019.9.1 How to Change Chassis Serial Number)


Skylarking to SDH:  If the XW6400 BIOS is like that on the Z210 then you can simply press CRTL-A right after entering BIOS.  Then go to Security tab/ System IDs/ and you should see some previously hidden fields.

Keep in mind that if your replacement motherboard is used (not “virgin”), the hidden data fields will have been previously defined.  If this is the case, you can't redefine most of these hidden fields. 

(SDH edit:  You can, however, at least change the Chassis Serial Number many times.  To do this navigate to Security tab, System IDs, move cursor into the Chassis Serial Number box, use space bar once to clear the used CSN there, turn on CapsLock, and enter the correct alphanumerics of the desired CSN update.  Then F10 to save, Accept, and F10 to save again on the way out of BIOS).

The assumed reason for this is that if people could simple update the Build ID and FeatureByte in BIOS and then perform a factory recovery they could get an OS version and other software loaded on their system that they had not paid for.

If you must re-enter these fields on a used motherboard you might be able to dump the contents of the BIOS flash memory and analyze it to determining where this hidden data is stored and what checksums are involved in protecting it.  It is doable but it's not a trivial task and needs some knowledge, time and hardware which I have little of.  Cheers.

Skylarking’s email response to a question from SDH:  Don't know about the XW6400 but for a Z210 (with J51 V01.35 BIOS), I have the following top main tabs when entering the BIOS via F10 key at boot:

 <File>    <Storage>    <Security>    <Power>    <Advance>

 F10 into BIOS, over to <Security> tab, down to <System IDs>.

Enter the <System IDs> option where you’ll normally find only the following four:

<Enter Asset Tag>   (user configurable from within BIOS normally)

<Enter Ownership Tag>   (same)

<Enter UUID>   (which is grayed out because it cannot be changed)

<Keyboard>   (English)

Now hit the ESC key to back out of this page (<System IDs> stays highlighted, then press CTRL + A, and then hit return to go back into <System IDs> which  now provides the following expanded 10 options for me:  Enter Asset tag     Enter Ownership tag     Enter UUID (which is grayed out)     Chassis serial number     Product name     Enter family name     SKU number     Enter Build ID     Enter Feature Byte     Keyboard


SDH EDIT:   You can just navigate to the Security tab and then down to highlight <System IDs>, then hit CTRL + A, and then hit ENTER.  This will get you to the larger menu hidden there.

For the xw6400 I was working with, with a new motherboard, the very top entry was “Enter Chassis Serial #” and the original one present was an odd “CZC717170CM6”.  I have seen these odd “C” entries only in brand new motherboards, and deduced that this means the original serial number was not edited after the “virgin” motherboard was installed.  This turns out to be accurate.  Hit the space bar once to delete that entire C serial number and  turn Caps Lock on to easily enter your correct chassis serial number (found on the side/back labels on the outside of the workstation).  Then I use F10 to save, and exit BIOS the usual way (also saving one last time properly on the way out of BIOS).  The new correct serial number then will show up in BIOS on reboot, and I even can change it back and forth.


If you buy a used motherboard with the original Chassis Serial Number in place this same method can be used to enter the corrected CSN from your workstation’s case labels.


Note that at least some of these 'hidden' fields seem to only allow data to be entered once (for a new motherboard where these fields are blank).  Any subsequent attempt at changes show up as changed  within this BIOS page as you type them but when you exit BIOS (saving changes properly on the way out) they always seem to revert back to their previous 'first' setting when you check back again in this hidden page.  That is, you only have one go at setting Build ID, Feature Byte (and I think also Chassis serial number and other hidden fields).  So, assuming this CTRL-A feature works on a XW6400 you’re likely not able to change Serial Number anyway, unless it is on a new motherboard.

If it's just tracking you want, and don't want HP updates to work as intended, you can enter any serial number or other tracking alphanumeric you want in the asset and/or ownership tag field .


SDH EDIT:  Skylarking’s comments above are generally true, but at least the Chassis Serial Number can be changed back and forth at will many times.  I have not checked to see if UUID can be changed but a number of the entries cannot be altered after the time of original setup.  One idea was to change the chassis serial number back to a C value and see if that unlocks access to changing the UUID.  I doubt that would work.  This all has to do with proper licensing.



Added info directly from HP:

Universal Unique Identifier (UUID):  "Can only be updated if the current chassis serial number is invalid."  The "invalid" state, for example, can be present if the serial number is from a brand new un-used motherboard.  These brand new motherboards come with a non-standard chassis serial number (starting with a C), and if the real chassis serial number has not yet been properly entered the fields may remain programmable until that happens.  The chassis serial numbers and UUID numbers are normally set in the factory and are used to uniquely identify the workstation.  There are situations where getting a new motherboard and keeping the same exact UUID and serial number may be necessary (for special application licensing purposes, for example).


I wonder if a chassis serial number can be changed back to a non-standard C-type serial number and whether this would enable the change of the UUID.  I doubt it, but it would be worth trying.  For this to work with DR licensing I believe you would need to know the MAC and the UUID of the licensed workstation, and hide the MAC via BIOS, and change the UUID via the Skylarking method on a brand new motherboard, and use a PCIe slot NIC programmed to the original licensed MAC.



HP Recommended

That is an odd serial number you have for your original v1 motherboard, starting with C..... as if it is a replacement motherboard that was installed but that no one ever properly branded after the replacement.  I have seen that before as explained in my post above.  And, the two Z620 v2 virgin motherboards I bought had such a Chassis Serial Number before I did the branding.  It does not matter for you because you know it has an old v1 boot block date proving you can't ever use it for v2 processors.


I would not blame anyone for bagging on the branding process..... it is not easy at all, and the motherboard runs just fine without it.  


On one side edge of the back face of the workstation there usually is a thin silver stick-on label that may have your original case serial number.  It is usually there and also on a top silver label. 

HP Recommended


original sticker from my hp z820 (sorry I blurred some numbers/capitals)

Thank you very much for all this information. The CZC.... serial is actually printed on my workstation. Funny.


The seller mentioned in his description for the virgin mainboard, that the serial AND product number has to be set. Your description does not mention that. There is

Enter Asset tag
Enter Ownership tag
Enter UUID (which is grayed out)
Chassis serial number
Product name
Enter family name
SKU number
Enter Build ID
Enter Feature Byte

Maybe it is Product name?

When all of this is empty on a 'new' mainboard, which I do not know yet, what do I have to insert?

One important information: I do not use the workstation with a windows recovery set from HP, so the 'license question' is not important for me.


HP Recommended

Check on the thin back edge label I told you about...... is the Chassis Serial Number there the same as you show?


A motherboard can be branded and still have the C type serial number I mentioned in my posts earlier if the installer did not enter the Chassis Serial Number during the branding.  You can do that any time to any value using the Skylarking mehtod.  However, your silver label picture above sure looks like that is what the workstation came with, or whether that could reflect the country of origin.  I don't work with the Z820 workstations but doubt all of them start with C.  You won't know what is or is not branded already until you dig into the process, with your new v2 motherboard installed.


So, you believe you are getting a virgin motherboard.  I have materials I can send you but I don't have a clean HowTo.  You will have to figure out that from my materials and so PM me with contact info.  Branding is truly a project for a HP Field Service Engineer, or for the top % of forum members here.


Since you won't be using a HP Recovery Disc set for install you don't really need to do anything but swap in your new motherboard.  However if you wish to have a challenging weekend of computer fun get in touch.  Take a clear picture of every label on your case......  top/bottom/sides/back.  All the necessary branding entries are on those but there are tricks .  If you choose to proceed now without branding take pictures and use very good tape to tape up out of the way each cable in sequence along the perimeter.  You don't want those popping loose during the project.


In the Z620 there is a rotating plastic vertical tab that keeps the motherboard from sliding over and then up and out..... it is not intuitive to rotate that to give just enough space to slide the motherboard towards the tab to free it from its case slots.  The Z820 might use that same mechanism...

HP Recommended

Hello there,

thank you again for all this information and your help. The hardware exchange if the HP z820 motherboard is very well documented here:

HP Z820 Workstation - Removing and Replacing the System Board 


I checked all stickers on my workstation, the back one and also the bottom one is showing the same CZC.... number as I already mentioned. On the bottom, there is also a sticker with the Build ID (BID=...) and the Feature Byte (FeatureByte=...). The BID is showing for two numbers just blank **, I checked in the BIOS Security/System IDs section with the CTRL+A hotkey, if they are the same there and they are. In the BIOS Security/System IDs nine lines are filled with information, only the 'Ownership Tag' is empty.


When I brand the new mainboard with just the same numbers/capitals etc. found in the section Security/System IDs ( CTRL+A hotkey) it should be fine. What do you think?

HP Recommended

if the board is virgin (unused) it will simply prompt you upon every boot to enter the information and not let you proceed until said information is entered


if you have a existing OS that has software that uses the board UUID as part of it's activation/licensing or OS setup it's recommended you clone the old boards UUID (which is part of the bios information) onto the new one and do the same for the units serial number which is found on the case sticker

HP Recommended

To OP.....  I'm happy to send you my materials if you PM me.  You'll need to do what I did.... learn from the materials, do it, and then forget it until the next time.  It is too complex to try to step you through the process over this forum.  For example, even one wrong upper vs lower case or the miss of a space will cause the code you enter to fail.  It is as if HP really did not want a non-FSE to be messing with this.  Even the font they use on one of the long critical alphanumerics can be hard to differentiate upper from lower case letters.


You also can dig out the materials I did with Google but the problem there is that the HP branding methods have changed over time and thus there is a mismash of info out there.

† The opinions expressed above are the personal opinions of the authors, not of HP. By using this site, you accept the <a href="https://www8.hp.com/us/en/terms-of-use.html" class="udrlinesmall">Terms of Use</a> and <a href="/t5/custom/page/page-id/hp.rulespage" class="udrlinesmall"> Rules of Participation</a>.