I am setting up a system that I am going to clone a very similar Windows 10 Pro system to once it's hardware is fully tested. Currently it has a Windows 10 Pro install (the motherboard has an embedded OEM key, both systems do) that's just a temporary install that I am testing and messing around with until the system is fully tested and configured hardware-wise and then I will clone my previous system onto it.
Before I do that however, I was thinking it would be a good idea to upgrade this current temporary install to Windows 11 to get familiarized with it since I will have to upgrade by 2025 anyway. It's an older system so it doesn't meet the minimum CPU requirements (Xeon 2667 v4), but it does support TPM 2.0 and Secure Boot. I heard that apparently if Windows 10 is already installed it will let you upgrade it to 11 even if these requirements are not met, but it won't let you do that on a fresh install.
One thing I noticed however when I was setting up the system was that it had TPM 1.2, not 2.0. But that there was a firmware update for both TPM 1.2 and 2.0, the 1.2 just updated the 1.2 one to a different version, but the 2.0 one replaced the TPM 1.2 firmware with 2.0. (I had no idea it was even possible for a system to update TPM 1.2 to 2.0 like that, I assumed that 1.2 and 2.0 would be separate from each other instead of 2.0 replacing 1.2) but when I tried I ran into an error that there was already a key or it was registered or something and I had to go through a process to basically wipe the TPM information blank before I could update it (this was a used system).
This made me think, so then would upgrading to Windows 11 write something to the motherboard that could make it problematic once I clone my older Windows 10 system to it? And/or would it lead to issues once I have to update that to 11? I am planning to leave TPM off for now anyway while I am still just using it as a temporary test install when I try to upgrade 10 to 11, but I don't want to leave traces of the old install on the motherboard once I clone the other system to it. I was under the assumption that nothing that the OS does is stored to or changed on the motherboard at all and only the BIOS ever changes anything there, but with UEFI and TMP and other changes nowadays since I am still very much used to an older era of systems I am not so sure anymore.
Before I do that however, I was thinking it would be a good idea to upgrade this current temporary install to Windows 11 to get familiarized with it since I will have to upgrade by 2025 anyway. It's an older system so it doesn't meet the minimum CPU requirements (Xeon 2667 v4), but it does support TPM 2.0 and Secure Boot. I heard that apparently if Windows 10 is already installed it will let you upgrade it to 11 even if these requirements are not met, but it won't let you do that on a fresh install.
One thing I noticed however when I was setting up the system was that it had TPM 1.2, not 2.0. But that there was a firmware update for both TPM 1.2 and 2.0, the 1.2 just updated the 1.2 one to a different version, but the 2.0 one replaced the TPM 1.2 firmware with 2.0. (I had no idea it was even possible for a system to update TPM 1.2 to 2.0 like that, I assumed that 1.2 and 2.0 would be separate from each other instead of 2.0 replacing 1.2) but when I tried I ran into an error that there was already a key or it was registered or something and I had to go through a process to basically wipe the TPM information blank before I could update it (this was a used system).
This made me think, so then would upgrading to Windows 11 write something to the motherboard that could make it problematic once I clone my older Windows 10 system to it? And/or would it lead to issues once I have to update that to 11? I am planning to leave TPM off for now anyway while I am still just using it as a temporary test install when I try to upgrade 10 to 11, but I don't want to leave traces of the old install on the motherboard once I clone the other system to it. I was under the assumption that nothing that the OS does is stored to or changed on the motherboard at all and only the BIOS ever changes anything there, but with UEFI and TMP and other changes nowadays since I am still very much used to an older era of systems I am not so sure anymore.