@bonienl The VM GUI editor is hard coded to set the thread count to 1 if it detects an AMD processor in libvirt.php // detect if the processor is AMD, and if so, force single threaded $strCPUInfo = file_get_contents('/proc/cpuinfo'); if (strpos($strCPUInfo, 'AuthenticAMD') !== false) { $intCPUThreadsPerCore = 1; } This was due to AMD reporting no support for hyperthreadding in a VM. With UNRAID 6.8.1 RC1, hyperthreadding is supported with CPU passthrough as is (and CPU cache) if the