* power status after ac power loss * SATA ahci mode enabled * DDR speed * advanced ram timings * enables NICs * cpu overvoltage enabled * iommu enabled status

And others I’m forgetting.

X399 IOMMU support is completely broken, as well as ASPM. These options must be disabled to even successfully install Windows 10.

The X399 Taichi bios shows me tons of options for hardware/controllers that aren’t even physically present.

These motherboards cannot run RAM at the rates speeds due to the infinity fabric design. Look at the compatibility list AsRock published. They cannot achieve 2666MHz without jumping up to ram rates for 3200MHz, if I recall correctly. That’s because X399 is built as two separate sockets that happen to share a heatspreader and lga connection, and the interconnect operates at the same speed as the ddr bus; it just can’t keep up with tight timings.

After updating to Firmware v2, 4/5 Times the bios says “no connection” when trying to check for online updates (despite the wired connection in both ports plus a 10gbe pcie card), and a full power cycle is needed to try again.

This is the first chipset I’ve seen that won’t let me run a stick of ram at a slower speed (but it let me run other ram at slower speeds, so I’m not sure why) and fails to post if I set my ram to less than the XMP 2 setting manually.

The bios is built for gamers and overclockers. The options to enable OC are “auto” or “manual” and there is no “stock” or “disabled” option.

This wasn’t a platform built for stability. Motherboard manufacturers are treating ThreadRipper as if it were Ryzen, as if we were all gamers and this wasn’t a workstation chipset.

Intel lets you run Core i7 on its server boards. AMD won’t let me use a motherboard sold for Epyc with my ThreadRipper CPU. Nor should they have to.. except my current options are all crap.

My biggest problem of all is that X399 (not just the Taichi) randomly stops recognizing certain PCI-E cards. My PCI-E 10gbe x520-da2 NIC worked ok for a couple of weeks hen suddenly wasn’t seen any more. I thought it was the card and bought a new one. Same problem. I thought it was the os so I installed another. Same problem. I thought it was the bios so I reset it. Same problem. I manually toggled each option pertaining to PCI in the bios and rebooted to test between each one. Same problem.

Took a look on NewEgg. All the x399 boards have 3 star reviews at best, and are filled with similar PCI-E complaints and “worked for a month then stopped working” across all the manufacturers and models. Which isn’t saying much, since there are only a dozen or so, really.