(In reply to comment #0)
> 
> https://bugs.freedesktop.org/show_bug.cgi?id=66963 was fixed but here comes
> new problem. When booting into X(KDE splash screen), it seemed to
> freeze(even after a cold reset), but I managed to switch to tty and get the
> dmesg. Xorg log is fine. In the end I have to shutdown.
> This situation seems to be more often than normal booting.

Are you saying this same problem happens even without dpm enabled?