Cascade will be too cold they had cold bug around -50 - -60 most. Casecade no good for this without maybe some aluminium shimms.
My top Kabylake's are available in the 5.1 bundles. Buy one no issue there. We sold several already most leaving at 5.2ghz for 24-7.
I was testing a prototype new system today with Kabylake at 5.6+ 24-7.
My best three I am keeping for benching.
Good god
5.6 24/7? How much would one be looking at paying for a bundle like this?