TPM PPI 0 - white screen doesn't go away

[Bernhard__H]

TPM is bringing my PC to its knees...

I got the message to enable TPM2 for Windows 11 and tried to enable TPM via tpm.msc - "prepare TPM" ("TPM vorbereiten" in German) since I had a recent Bios update just before (2.59) I thought that this should work. Well...no, it did not. After the reboot I am greeted by a white screen just displayiing "TPM PPI 0" with no possibility to press anything.

I tried removing all devices and pressing the CMOS clear button, updating the firmware (same boot loop as in https://h30434.www3.hp.com/t5/Business-PCs-Workstations-and-Point-of-Sale-Systems/HP-Z840-TPM-PPI-Wh...- but in my case, I am always back to the white screen).

I cannot bring up the BIOS with ESC or F10, flashing the BIOS by setting the jumper 33 is somewhat working, the screen shows the flashing of the bios, then the PC restarts and flashes again, unless you turn it off I guess it will continue to reflash. 

I have found no other mention of this problem than the one thread which did not work in my case. 

Also: seems downgrading bios to 2.57 or 2.58 does not work, either. If I have a USB stick with 2.57/2.58 in, it beeps 8 times, then does the first "run", then instead of starting the second and flasing the bios, it gives an endless loop of 8 beeps. Popping in a 2.59 again, it re-flashes/recovers as previously.

WIN+B while powering up doesn't work, a bootable disk also doesn't work. Just that silly TPM PPI screen with a simple "0" instead of the message with F1/F2 (pressing any key does also not work at that screen).

Oh, also removing the CMOS battery does not reset anything it seems (in case that reset button wasn't working). I am not getting asked to reset time&date after that, just the same TPM PPI 0 screen.

I am truly amazed - it seems that clearing TPM only works with a tool from windows. 

Grateful for any help...

[Bernhard__H]

Well, calling HP Support proved to be fruitless - since the system is out of care pack since mid 2021, and they did not find any clue in their internal database, they recommended to get another motherboard (which is what they would do, if it were in support).

This is all very unsatisfying, to be stuck with a bricked system because I clicked on a TPM option in Windows. Loss of data when using bitlocker and TPM is changed, that I can accept - but just being locked out and no support tools available, Is here someone with a deeper knowledge of HP tools who can tell me if it's possible to reset TPM though the bios bootblock recovery process (or any other process not requiring BIOS access)?

[Bernhard__H]

-consolidated-

[Bernhard__H]

I can see that this is a very peculiar problem - I have made one discovery, though.

If I set Jumper 35 ME/AMT flash override to enable ME flashing, something changes. The "0" otherwise displayed in the middle of the screen disappears and it's fully blank except the TPM PPI message. 

I wonder if the ME firmware can be updated via recovery, too?

[Bernhard__H · Accepted solution]

OK, WOW...

I gave it a last chance - set the ME/AMT Jumper to "enable", clear CMOS, reboot. White Screen without the "0".

Out of fustration, pressed F1. Computer reacts and reboots...*blink*

Then some message about time, and changed secure boot with confimation...and then windows boots. TPM still at 1.2 - but hey...

So it seems that the messages are lost somewhere ("0" probably meaning "hey you need to enable ME flashing!" and "nothing" meaning "press F1 to do this and F2 to do something else" and HP should correct that in the next bios release.