Install Nvidia drivers and black screen issue for Ubuntu 14.04 on a dual graphic cards laptop, on a sole Nvidia desktop, etc

I update the driver to 375.26 and all good. Frustrated. Thank NVidia. It takes me more than half a year to troubleshoot the issue. With Intel graphic card we still can run RViz but hangs in Gazebo and PCL.

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nVidia drivers.
should be easier on a desktop but seems many problems for dual graphic cards laptops. Up to now none of the post exactly describes the display problems with my laptop.

Check this first. Before start, be prepared for a shell only environment cos it is easy to crash the graphic user interface.
How to install the latest Nvidia drivers on Ubuntu 14.04 Trusty Tahr

It is important to know the current status of the graphic card

➜ ~ lspci -vnn | grep -i VGA -A 12

00:02.0 VGA compatible controller [0300]: Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) (prog-if 00 [VGA controller])
 Subsystem: Sony Corporation Device [104d:909a]
 Flags: bus master, fast devsel, latency 0, IRQ 30
 Memory at b9000000 (64-bit, non-prefetchable) [size=4M]
 Memory at c0000000 (64-bit, prefetchable) [size=256M]
 I/O ports at 7000 [size=64]
 Expansion ROM at <unassigned> [disabled]
 Capabilities: <access denied>
 Kernel driver in use: i915

01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GK107M [GeForce GT 640M LE] [10de:0fd3] (rev a1) (prog-if 00 [VGA controller])
 Subsystem: Sony Corporation Device [104d:909a]
 Flags: bus master, fast devsel, latency 0, IRQ 7
 Memory at b8000000 (32-bit, non-prefetchable) [size=16M]
 Memory at a0000000 (64-bit, prefetchable) [size=256M]
 Memory at b0000000 (64-bit, prefetchable) [size=32M]
 I/O ports at 6000 [disabled] [size=128]
 Expansion ROM at <ignored> [disabled]
 Capabilities: <access denied>

You can see that intel is properly installed but NVidia is not working.

sudo apt-get install nvidia-331

it will automatic install nvidia 340.

black screen. will be freeze, just no display. can here the sound, can change to tty1 by press ctrl alt + f1. did not check whether the display is on another screen. remember last time, there s no display because the main display is by default an external one.

can be rescued by

sudo prime-select intel

Is blacklist nouveau necessary?
Even I have a blacklist.nvidia340 but I still install nouveau drivers...
and the system freeze.

➜ ~ lspci -vnn | grep -i VGA -A 12

01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GK107M [GeForce GT 640M LE] [10de:0fd3] (rev a1) (prog-if 00 [VGA controller])
 Subsystem: Sony Corporation Device [104d:909a]
 Flags: bus master, fast devsel, latency 0, IRQ 16
 Memory at b8000000 (32-bit, non-prefetchable) [size=16M]
 Memory at a0000000 (64-bit, prefetchable) [size=256M]
 Memory at b0000000 (64-bit, prefetchable) [size=32M]
 I/O ports at 6000 [size=128]
 Expansion ROM at <ignored> [disabled]
 Capabilities: <access denied>
 Kernel driver in use: nvidia

check this post...
https://vxlabs.com/2015/02/05/solving-the-ubuntu-14-04-nvidia-346-nvidia-prime-black-screen-issue/

Three ways to install Nvidia and the way on "F**k Nvidia" begins...

Install from official website fails. 

check the graphic card

if you wanna check whether your laptop is suitable for OpenGL,

/usr/lib/nux/unity_support_test -p

and you will see something like

OpenGL vendor string:   NVIDIA Corporation
OpenGL renderer string: GeForce GTX 660/PCIe/SSE2
OpenGL version string:  4.4.0 NVIDIA 340.96

Not software rendered:    yes
Not blacklisted:          yes
GLX fbconfig:             yes
GLX texture from pixmap:  yes
GL npot or rect textures: yes
GL vertex program:        yes
GL fragment program:      yes
GL vertex buffer object:  yes
GL framebuffer object:    yes
GL version is 1.4+:       yes

Unity 3D supported:       yes

if the unity 3D supported is no, definitely it won't work well.

Some issues related to the graphic drivers, is already in the wiki. And pub key, dpkg lock,

Rather than Nvidia, Google is our best friend forever. Most of the problems can be solved by google and askubuntu forum so will not repeat here. For different hardware settings and different system configuration, just tackle the problem when it happens.

after disable gpu, can enter system but unity_support_test -p

Xlib:  extension "NV-GLX" missing on display ":0".
X Error of failed request:  BadValue (integer parameter out of range for operation)
  Major opcode of failed request:  155 (GLX)
  Minor opcode of failed request:  3 (X_GLXCreateContext)
  Value in failed request:  0x0
  Serial number of failed request:  27
  Current serial number in output stream:  28

without gpu, cannot run rviz.

sudo apt-get install nvidia-current-updates

sudo nvidia-xconfig

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Again, Nvidia driver problem. on a desktop with sole Nvidia graphic card, gtx1060.

Phenomenon: We can see the welcome screen ,after enter the password, the display blackout and back to the welcome screen again... so it is a deadlock.

Installed 367.XX, cannot be solved. Tried 375, same problem.

When switched to tty1, an error is printed on the screen:

TSSI upper saturation

Ok, I am not sure about this error and google cannot give me much useful info.