5700X on C6H - Error D6

[pycta]

Hi,
i have a rather puzzling problem:
I want to upgrade my build (C6H, Nvidia 1070Ti, Ryzen 5 2600) to a Ryzen 5700X. I upgraded the C6H to the latest BIOS (8801) and swapped the CPU.
I got to some fTPM-Screen, but after that - nothing. The Display shows code D6 (GPU Error).
Swapping back in the 2600 and everything works great. After many back-and-forth-swaps and messing in the BIOS, I was getting the 5700X to work once, but then i had to reset the CMOS again and I can't get it working again. I tried everything:
-Disconnecting everything
-Countless CMOS-Resets
-Upgrading the 1070TI-Firmware (already up to date)
-Disable FastBoot, CSM, Secure Boot

Does anyone have an idea what i'm doing wrong?

Thanks!

[Silent_Scone]

Hi @pycta 

Try going to Advanced > AMD fTPM configuration and disable fTPM. 

Alternatively, see if the issue persists using the second PCIE slot.

[pycta]

There is no option to disable the TPM, only switching between firmware and discrete TPM is possible.
And there is something even more strange:
I noticed the options "Disable CSM" and "Enable Discrete TPM" don't keep - they revert after saving and restarting...

[pycta]

So, i tried flashing an older BIOS version (8601) and the system was working with the 5700X. I was able to clear the fTPM-Keys and startet tuning up my system again. However, after the first power cycle, the error is back now...

[pycta]

I tried the second slot, even with a different GPU - still no video and "d6" code.

[Silent_Scone]

I'm starting to suspect the CPU, personally.

[gupsterg]

@pycta 

If you keep CSM Enabled does it resolve issue?