Simon Farnsworth (simon.delete@this.farnz.org.uk) on June 20, 2022 10:09 am wrote:
> Note that PCIe is carried in Thunderbolt 3 connectors - both Black Magic Design and
> AVID sell Thunderbolt 3 equivalents of their PCIe cards, at a price. And both StarTech
> and Sonnet do PCIe cages for Thunderbolt 3 machines - the StarTech one is about $350
> retail - to let you use an existing PCIe card with your Thunderbolt 3 computer.

Blackmagic will sell you a Ultrastudio Thunderbolt connected video I/O device for 4K, however for 8K video Thunderbolt 3 or 4 does not have enough bandwidth and you need a Decklink PCI-E card or AJA Kona 5.

It seem that Avid now qualify exactly 1 thunderbolt enclosure for a 3 card HDX system that being a Sonnet Echo III desktop. Most people don't bother though and use a machine with physical PCI-E slots. These kind of solutions came in to existence originally for the 'trash can' Mac Pro of 2013 which were so universally hated that people hung on to the previous machines like grim death until Apple relented and produced the 'cheese grater' version.

> a bit more - but any price-sensitive professional user won't be buying a Mac Pro to begin with.

The kind of market Apple is addressing with the Mac Pro is not price sensitive for the computer as the cards we are talking about and the stuff they are plugged into makes the computer look cheap.