It turns out that I CAN install windows 11 on my main machine, not that I will for the next little while. Need to wait to make sure that all the vendors are going to support it.
When I first tried to install however, the PC Health Check app (Only download from MS, no one else!) gave me the very un-helpful, no your PC doesn't meet the requirements without telling me why.
I had to go through the process, one by one, to see which of the requirements my computer didn't meet. Was is the processor? Nope
Maybe the graphics card? Not that either.
Maybe its the TPM, and sure enough there was no TPM module installed. Of course that was a pain to figure out. The fastest I found was to type Security Processor in the search bar.
TPM v2.0 Security Processor
When I did that the first time the page was empty indicating that there was no TPM chip on my motherboard. My initial reaction was of mild disappointment, but like I said at the start. I wasn't going to install windows 11 on this machine anyway and would likely upgrade the motherboard anyway before the end of life of Windows 10 in 2025.
But then I remembered that this machine was pretty much the best you could get 3yrs ago, there is no way that microsoft would obsolete software this "new", so I did what any self respecting engineer would do, I dug into the bios.
My first attempt broke the boot process, which has the potential to ruin my day, but defaulting the BIOS back and then trying again, I was able to enable the TPM module and now I have a result in the security processor.
Don't give up immediately
So if you have a relatively new computer and the PC Health Check app gives you a thumbs down, check for yourself. It could be as easy as a checkbox in your BIOS. But remember to have a good backup in case you check the wrong check box.
I mean, it wouldn't be that hard for Microsoft to check a motherboard database to see if there is a TPM on the board and then tell you that its just not enabled rather than implying that you have to buy brand new hardware. The same would go for the processor or graphics requirements.
They have to check to see what's there, might as well state WHAT doesn't meet the requirements.