HELP - AMD Microcode issues, Kernel ACPI mode, screen tearing, single thread use (100%) instead of 24

[Svyatko]

Did someone already experienced this and knows how to solve it, please?

I have this status message in retbleed under /sys/devices/system/cpu/vulnerabilities/ - AMD mitigation “untrained return thunk” enabled and hyperthreading disabled and my kernel parameters are sat (Boot Loader) like this: acpi=off retbleed=unret, nosmt splash=off security=apparmor CPU Mitigation=manually If I switch the acpi to “on” the system froze on boot after the very last line “VCN decode is enabled in VM mode and JPEGdecode is enabled in VM mode”. I can’t figured out where the problem…

Did someone already experienced this and knows how to solve it, please?

ILL Zen 3 family have some enhancements - try to use Zen 3 CPUs ILL VRMs on MSI B450M MORTAR MAX are rather weak, so don’t use CPUs with 12 or 16 kernels. And you’re using AMD Ryzen 9 3900X - bad choice for that mobo. Also use 2nd and 4th slot when using two memory modules (RTFM, man). Post inxi -amz to be sure. Message: For most reliable report, use superuser + dmidecode.