You have B350 vs the A320 mentioned, correct?
Now I'm confused about 5000 CPU support, as the A320 notice is recent, so wouldn't B350 have been first?
Not sure about TPM 2.0, so hope it is present.
Motherboards without support will require a TPM add-in card for W11... unless you disable the TPM requirement, which I have seen discussed.
1: I don't think there is any B350 motherboards yet supporting the Ryzen 5000 series CPUs. Only A320 motherboards so far.
2: However, I also found there is a recent updated BIOS for my B350 board when I looked on the website. But of course that's primarily just a defaults change so as to smooth the installation of Win11 by enabling TPM by default.
Then, what I discovered about TPM support is it seems to be fully functional - which I hadn't expected to find given the TPM slot in the motherboard is unpopulated. My conclusion is the required hardware is present in the Ryzen 1700X - has been there all along.
But, finally, the updated BIOS clearly contains more than just a default setting flipped. The menus haven't changed between the two BIOS versions but the compressed size has.
PS: Speculation online, for why only the A320 is getting this support, seems to be that the cheapest end of the market aren't likely to upgrade the whole kit to move from Zen/Zen+ to Zen3. Therefore the reasoning goes that AMD, and the board makers, are strategically providing this to get more CPUs, and RAM, sold without cutting into the newer motherboard sales.