Eu tenho um ASUS X53S fornecido com o Windows 7, meses atrás, atualizado para o Windows 10, e há algumas semanas instalei o Ubuntu nele.
Quando inicializo o Ubuntu, vejo essas mensagens por muitos segundos (talvez um minuto)
[ 2.484345] usb 4-1-port3: over-current condition
[ 2.692231] usb 4-1-port4: over-current condition
onde os números nos colchetes mudam de inicialização para inicialização.
Quais são essas mensagens?
A saída od lsusb é
enrico:~$ lsusb
Bus 004 Device 004: ID 046d:c52f Logitech, Inc. Unifying Receiver
Bus 004 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 004: ID 0bda:0139 Realtek Semiconductor Corp. RTS5139 Card Reader Controller
Bus 003 Device 003: ID 058f:a014 Alcor Micro Corp. Asus Integrated Webcam
Bus 003 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
As 3 portas USB (1 azul e 2 pretas) funcionam corretamente.
EDIT O comando sugerido por @mchid fornece este resultado
enrico:~$ systemd-analyze blame
16.734s gpu-manager.service
9.536s NetworkManager-wait-online.service
8.225s plymouth-quit-wait.service
8.031s dev-sda6.device
7.537s apparmor.service
6.484s ModemManager.service
5.322s systemd-tmpfiles-setup.service
5.040s accounts-daemon.service
4.978s NetworkManager.service
3.897s teamviewerd.service
3.308s alsa-restore.service
3.308s systemd-user-sessions.service
3.307s apport.service
3.304s avahi-daemon.service
3.217s irqbalance.service
3.216s pppd-dns.service
3.215s speech-dispatcher.service
2.396s plymouth-start.service
2.053s lightdm.service
2.040s systemd-udevd.service
1.296s systemd-tmpfiles-setup-dev.service
1.234s dns-clean.service
1.174s systemd-journal-flush.service
lines 1-23...skipping...
16.734s gpu-manager.service
9.536s NetworkManager-wait-online.service
8.225s plymouth-quit-wait.service
8.031s dev-sda6.device
7.537s apparmor.service
6.484s ModemManager.service
5.322s systemd-tmpfiles-setup.service
5.040s accounts-daemon.service
4.978s NetworkManager.service
3.897s teamviewerd.service
3.308s alsa-restore.service
3.308s systemd-user-sessions.service
3.307s apport.service
3.304s avahi-daemon.service
3.217s irqbalance.service
3.216s pppd-dns.service
3.215s speech-dispatcher.service
2.396s plymouth-start.service
2.053s lightdm.service
2.040s systemd-udevd.service
1.296s systemd-tmpfiles-setup-dev.service
1.234s dns-clean.service
1.174s systemd-journal-flush.service
1.127s systemd-tmpfiles-clean.service
lines 1-24...skipping...
16.734s gpu-manager.service
9.536s NetworkManager-wait-online.service
8.225s plymouth-quit-wait.service
8.031s dev-sda6.device
7.537s apparmor.service
6.484s ModemManager.service
5.322s systemd-tmpfiles-setup.service
5.040s accounts-daemon.service
4.978s NetworkManager.service
3.897s teamviewerd.service
3.308s alsa-restore.service
3.308s systemd-user-sessions.service
3.307s apport.service
3.304s avahi-daemon.service
3.217s irqbalance.service
3.216s pppd-dns.service
3.215s speech-dispatcher.service
2.396s plymouth-start.service
2.053s lightdm.service
2.040s systemd-udevd.service
1.296s systemd-tmpfiles-setup-dev.service
1.234s dns-clean.service
1.174s systemd-journal-flush.service
1.127s systemd-tmpfiles-clean.service
1.039s grub-common.service
1.007s console-setup.service
932ms script_enrico.service
915ms systemd-logind.service
910ms rsyslog.service
882ms systemd-modules-load.service
729ms ifup-wait-all-auto.service
713ms wpa_supplicant.service
642ms polkitd.service
636ms networking.service
605ms systemd-backlight@backlight:acpi_video1.service
588ms udisks2.service
585ms systemd-journald.service
527ms [email protected]
510ms systemd-udev-trigger.service
502ms systemd-random-seed.service
457ms colord.service
440ms plymouth-read-write.service
436ms ufw.service
399ms systemd-setup-dgram-qlen.service
398ms dev-hugepages.mount
348ms resolvconf.service
301ms kmod-static-nodes.service
277ms upower.service
257ms systemd-update-utmp.service
243ms dev-mqueue.mount
239ms systemd-backlight@backlight:acpi_video0.service
233ms systemd-remount-fs.service
208ms systemd-sysctl.service
205ms [email protected]
156ms sys-kernel-debug.mount
134ms systemd-vconsole-setup.service
132ms dev-disk-by\x2duuid-66a710be\x2d064b\x2d43e2\x2d9426\x2d7e7291463cbf.swap
95ms systemd-timedated.service
83ms systemd-backlight@backlight:intel_backlight.service
72ms ondemand.service
62ms systemd-hostnamed.service
61ms kerneloops.service
53ms [email protected]
48ms systemd-timesyncd.service
34ms systemd-localed.service
33ms thermald.service
4ms ureadahead-stop.service
3ms rtkit-daemon.service
2ms systemd-update-utmp-runlevel.service
2ms rc-local.service
2ms sys-fs-fuse-connections.mount
lines 32-71/71 (END)
713ms wpa_supplicant.service
642ms polkitd.service
636ms networking.service
605ms systemd-backlight@backlight:acpi_video1.service
588ms udisks2.service
585ms systemd-journald.service
527ms [email protected]
510ms systemd-udev-trigger.service
502ms systemd-random-seed.service
457ms colord.service
440ms plymouth-read-write.service
436ms ufw.service
399ms systemd-setup-dgram-qlen.service
398ms dev-hugepages.mount
348ms resolvconf.service
301ms kmod-static-nodes.service
277ms upower.service
257ms systemd-update-utmp.service
243ms dev-mqueue.mount
239ms systemd-backlight@backlight:acpi_video0.service
233ms systemd-remount-fs.service
208ms systemd-sysctl.service
205ms [email protected]
156ms sys-kernel-debug.mount
134ms systemd-vconsole-setup.service
132ms dev-disk-by\x2duuid-66a710be\x2d064b\x2d43e2\x2d9426\x2d7e72914
95ms systemd-timedated.service
83ms systemd-backlight@backlight:intel_backlight.service
72ms ondemand.service
62ms systemd-hostnamed.service
61ms kerneloops.service
53ms [email protected]
48ms systemd-timesyncd.service
34ms systemd-localed.service
33ms thermald.service
4ms ureadahead-stop.service
3ms rtkit-daemon.service
2ms systemd-update-utmp-runlevel.service
2ms rc-local.service
2ms sys-fs-fuse-connections.mount
EDIT2 Com os drivers de vídeo alterados (na verdade, o driver testado é nvidia-352), as linhas que eu leio na reinicialização são as seguintes
[ 2.484345] usb 4-1-port3: over-current condition
[ 2.692231] usb 4-1-port4: over-current condition
fsck from util-linux 2.26.2
/dev/sda6: clean, 421817/3842048 files, 4507321/15359744 blocks
onde os números entre colchetes e os dois numeradores na última linha mudam de inicialização para inicialização.