MSWX VM refuses to boot or bootloops on cpu change

There is one ms windows vm which behaves quite peculiar. Changing the CPU away from anything kvm64 (> host) results in an inability to boot. Even a reboot into safe mode use msconfig does not work as per usual.

Despite having configured a windows10 .iso to boot from the 'press any key to boot from cd ...' works neither.

As soon as the CPU is reverted to kvm64 (or qemu64) the VM boots normal again and the keyboard is now also responsive again

Tripple checked: VM protection is NOT on

using monitor: sendkey f8 5000
also does not work

there is no keyboard input working, except for the ESC key which permits to enter UEFI setup
Last edited:


Proxmox Staff Member
Staff member
Feb 1, 2016
can you post the output of 'pveversion -v' and the vm config? (qm config ID)

also does it work with a linux iso ?


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