So I am doing a pretty extensive test on existing system as follows:
1.)  Save off previous chainstate, blocks (bitcoin-core db) and restart from 0.
2.)  Now noted that initial progress to 50% or so is good, normal.
3.)  Once it starts slowing down I am stopping the bitcoind.service for 12 hours, giving it a rest.  This is just in case there is some kind of weird throttling going on.
4.)  After rest period restarting bitcoind.service.
5.)  If slow, then I am going to order this -> Beelink SER5 MAX RYZEN 7 5800H Mini pc office + Ram32GB + Storage 1TB

It is looking like about to order it, just waiting to confirm that progress is now slow .....

The surprising aspect for me is normally things either work or they don't.  This is one of those particular things that becomes more and more resource consuming as it goes along, still working but going slower and slower.