I created a reddit post but also will place one here. PCI Passthrough is completely broken on threadripper and the X399 platform. There is not a single case reported of being succesful. The tech reviewer who was supposed to post a video showing it has been radio silent. I can't believe we have to deal with 0day support when a MAJOR use case of threadripper is to have plenty of VM's.
Will provide any information necessary if we have dev cooperation but I'll be RMA'ing at the end of my 30 days if theres no patch in place.