The latest Windows 10 AMD Microcode update that was shipped is causing serious issues with my Asus STRIX X399-E motherboard. After performing BIOS downgrades and other attempts (before a total reinstall of the OS), I removed the mcupdate_AuthenticAMD.dll file from System32 and everything returned to normal.
- Very sluggish system. High amounts of 'DPC' Latency
- Slow booting. Takes nearly 3x longer than it should with an m.2 SSD
- Shutting down the computer causes it to no longer reboot. I have to reset the CMOS jumper for it to work again.
- The shutdown appears to corrupt something in the EFI settings, because I have to reset the BIOS every time to get the computer to power on.
After removing the microcode update files, everything returns to normal.
Performing some basic analysis on the vague microcode file, it appears this is another attempt at fixing the specter later variants and it's not doing a very good job, and it's corrupting some other things.
There seems to be some kind of regression in the microcode update file, which is not unusual (but damaging since we end users are at the Mercy of Windows 10 automatic updates to plague our systems with performance problems)