4 ms·

Perhaps they meant that downgrading is not possible without a reboot.

• quintushoratius 7y ago
  Loading microcode on a CPU (without patching the firmware) takes effect immediately. The update is lost immediately upon reboot and must be reapplied each time.
  • shawnz 7y ago
    Right, but can you load an older microcode after a newer microcode has already been loaded, without rebooting?