Второй монитор, больше не работающий над Ubuntu 14.04 [Intel]

Мой ноутбук является Acer Aspire M, и я раньше подключал второй монитор через HDMI регулярно. Приблизительно месяц назад это просто прекратило работать. Я действительно не знаю ничего, что я могу сделать, таким образом, любая справка значительно ценилась бы.

Сегодня я заметил, что, когда я подключал второй монитор, следующие сообщения открывались в TTY1, который я также нашел в kern.log

Jul 25 17:38:44 CNPq-Universal-2013 kernel: [122775.342394] ACPI: \_SB_.PCI0: Bus check notify on hotplug_event_root
Jul 25 17:38:44 CNPq-Universal-2013 kernel: [122775.800703] [drm:intel_dp_start_link_train] *ERROR* too many voltage retries, give up
Jul 25 18:41:15 CNPq-Universal-2013 kernel: [126528.997425] ACPI: \_SB_.PCI0: Bus check notify on hotplug_event_root
Jul 25 18:41:16 CNPq-Universal-2013 kernel: [126529.453129] [drm:intel_dp_start_link_train] *ERROR* too many voltage retries, give up
Jul 25 19:24:42 CNPq-Universal-2013 kernel: [129136.555803] ACPI: \_SB_.PCI0: Bus check notify on hotplug_event_root
Jul 25 19:24:42 CNPq-Universal-2013 kernel: [129137.016462] [drm:intel_dp_start_link_train] *ERROR* too many voltage retries, give up
Jul 25 19:30:39 CNPq-Universal-2013 kernel: [129493.589703] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:30:39 CNPq-Universal-2013 kernel: [129493.711272] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:30:39 CNPq-Universal-2013 kernel: [129493.736376] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:30:39 CNPq-Universal-2013 kernel: [129493.736391] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:30:39 CNPq-Universal-2013 kernel: [129493.761667] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:32:06 CNPq-Universal-2013 kernel: [129580.669767] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:32:06 CNPq-Universal-2013 kernel: [129580.763589] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:32:06 CNPq-Universal-2013 kernel: [129580.788761] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:32:06 CNPq-Universal-2013 kernel: [129580.788778] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:32:06 CNPq-Universal-2013 kernel: [129580.814130] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:02 CNPq-Universal-2013 kernel: [129636.517006] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:02 CNPq-Universal-2013 kernel: [129636.541971] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:02 CNPq-Universal-2013 kernel: [129636.541981] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:11 CNPq-Universal-2013 kernel: [129646.293981] Watchdog[2574]: segfault at 0 ip 00007fea75b0eb88 sp 00007fea66d22720 error 6 in libcontent.so[7fea753aa000+fd7000]
Jul 25 19:33:15 CNPq-Universal-2013 kernel: [129650.199365] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:15 CNPq-Universal-2013 kernel: [129650.263559] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:15 CNPq-Universal-2013 kernel: [129650.288593] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:15 CNPq-Universal-2013 kernel: [129650.288688] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:16 CNPq-Universal-2013 kernel: [129650.515649] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:21 CNPq-Universal-2013 kernel: [129655.576538] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:25 CNPq-Universal-2013 kernel: [129659.687743] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:25 CNPq-Universal-2013 kernel: [129659.713246] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:25 CNPq-Universal-2013 kernel: [129659.713313] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:25 CNPq-Universal-2013 kernel: [129659.787798] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:34 CNPq-Universal-2013 kernel: [129668.757269] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:34 CNPq-Universal-2013 kernel: [129668.823856] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:34 CNPq-Universal-2013 kernel: [129668.848773] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:34 CNPq-Universal-2013 kernel: [129668.848824] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:33:34 CNPq-Universal-2013 kernel: [129669.076025] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 248
Jul 25 19:34:16 CNPq-Universal-2013 kernel: [129711.120207] Watchdog[10511]: segfault at 0 ip 00007fc2caa07b88 sp 00007fc2bbc1b720 error 6 in libcontent.so[7fc2ca2a3000+fd7000]

Видел, что другой человек отправил эти детали, таким образом, я отправлю то же, если оно поможет.

$ uname -a
Linux CNPq-Universal-2013 3.13.0-32-generic #57-Ubuntu SMP Tue Jul 15 03:51:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux

$ cat /etc/*-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
DISTRIB_CODENAME=trusty
DISTRIB_DESCRIPTION="Ubuntu 14.04.1 LTS"
NAME="Ubuntu"
VERSION="14.04.1 LTS, Trusty Tahr"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 14.04.1 LTS"
VERSION_ID="14.04"
HOME_URL="http://www.ubuntu.com/"
SUPPORT_URL="http://help.ubuntu.com/"
BUG_REPORT_URL="http://bugs.launchpad.net/ubuntu/"

$lspci -vv
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09) (prog-if 00 [VGA controller])
    Subsystem: Acer Incorporated [ALI] Device 0712
    Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
    Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Latency: 0
    Interrupt: pin A routed to IRQ 45
    Region 0: Memory at c2000000 (64-bit, non-prefetchable) [size=4M]
    Region 2: Memory at b0000000 (64-bit, prefetchable) [size=256M]
    Region 4: I/O ports at 3000 [size=64]
    Expansion ROM at <unassigned> [disabled]
    Capabilities: <access denied>
    Kernel driver in use: i915

$ lsmod |grep video
uvcvideo               80885  0 
videobuf2_vmalloc      13216  1 uvcvideo
videobuf2_memops       13362  1 videobuf2_vmalloc
videobuf2_core         40664  1 uvcvideo
videodev              134688  2 uvcvideo,videobuf2_core
video                  19476  2 i915,acer_wmi