Thanks semiRocket.
I disabled the integrated intel VGA in the attempt to avoid those freezes. Didn't help.
Looked at the last boot logs (with intel disabled) and here what I found:
Code:
Nov 10 14:49:55 g-PC gnome-software-service.desktop[2542]: (org.gnome.Software:2542): Gs-WARNING **: Not already a started task for 0x555aed1f42d0~packagekit-refine
Nov 10 14:49:55 g-PC PackageKit[1749]: resolve transaction /115_edbaedac from uid 1000 finished with success after 338ms
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (**) Option "fd" "16"
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (**) Option "fd" "19"
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (**) Option "fd" "20"
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (**) Option "fd" "21"
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (II) AIGLX: Suspending AIGLX clients for VT switch
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (II) NOUVEAU(0): NVLeaveVT is called.
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (II) systemd-logind: got pause for 13:65
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (II) systemd-logind: got pause for 13:67
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (II) systemd-logind: got pause for 13:66
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (II) systemd-logind: got pause for 13:64
Nov 10 14:50:15 g-PC /usr/libexec/gdm-x-session[2055]: (II) systemd-logind: got pause for 226:0
Nov 10 14:50:15 g-PC kernel: nouveau E[ DRM] GPU lockup - switching to software fbcon
Nov 10 14:50:15 g-PC systemd[1]: Started Getty on tty3.
Nov 10 14:50:15 g-PC audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=getty@tty3 comm="systemd" exe="/u
Nov 10 14:50:15 g-PC systemd[1]: Starting Getty on tty3...
Nov 10 14:50:19 g-PC audit[1]: SERVICE_STOP pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=fprintd comm="systemd" exe="/usr/l
Line "Nov 10 14:50:15 g-PC kernel: nouveau E[ DRM] GPU lockup - switching to software fbcon" is marked in red.