unity - Clean install of Ubuntu 14.04 - Screen goes black after login, but mouse works

Disclaimer there are MANY questions on this topic and none of them apply to my situation.

Note the following:

1. The system previously ran Ubuntu 12.04 Desktop 32bit without issue.


2. This is a clean install, not an upgrade. Previous install was overwritten.


3. The black screen comes after logging in, not while booting.


4. The black screen comes regardless of the video driver, default(nouveau) or nvidia


5. It is not sporadic, it happens all the time.


6. It is not the result of returning from sleep or suspend.

I did a clean install of Ubuntu 14.04 Desktop 32bit (ubuntu-14.04-desktop-i386.iso) using liveUSB. The installation completes successfully, the system reboots, and I login. After logging in: the screen (with the background visible) flickers and eventually goes black (no background, no Unity Panel, no Unity Launcher), and I am able to move the mouse about the screen.

Just in case there is an update that resolves this, I switch to tty1 (Ctrl + Alt + F1) and type:

sudo apt-get update
sudo apt-get dist-upgrade

Reboot and same thing after logging in: the screen flickers and eventually goes black, and I am able to move the mouse about the screen.

The machine has nvidia graphics card, the GeForce FX 5700LE video card.

lspci | grep VGA
01:00.0 VGA compatible controller: NVIDIA Corporation NV36 [GeForce FX 5700LE] (rec a1)

So I install the nvidia 173 drivers:

sudo apt-get install nvidia-173

Reboot and now after logging in: the screen goes black, and I am able to move the mouse about the screen.

There are a number of post about Ubuntu 14.04 black screen after login, however they appear to be the result of upgrading from a previous version of Ubuntu and not a clean install. Regardless of that I tired the solution to that problem which is to purge the existing nvidia drivers via sudo apt-get remove --purge nvidia* . Not to my surprise after rebooting and logging in, I see the original behavior: the screen flickers and eventually goes black, and I am able to move the mouse about the screen.

I also tried to boot Ubuntu in recovery mode using failsafeX, I see a popup that says, "The System is running in low-graphics mode". No mouse is visible. I hit tab and enter. Next screen says, "What would you like to do?" and "Run in low-graphics mode for just one session" is selected. I hit tab twice, highlighting "OK" and hit enter. Next screen says, "Stand by one minute while the display restarts…". I hit enter. I see a shining black screen with no mouse.

I read that this is might be another issue since it occurs *after* entering your password on the login page.

Turns out unity does not support my video card. Seems there are a number of older NVIDIA cards that one would think would work with unity, but do not because they are blacklisted. For more info on this is found here.

I tested my video card with unity:

/usr/lib/nux/unity_support_test -p

returned:

OpenGL vendor string:   NVIDIA Corporation
OpenGL renderer string: GeForce FX 5700LE/AGP/SSE2
OpenGL version string:  2.1.2 NVIDIA 173.14.39
Not software rendered:    yes
Not blacklisted:          no
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:       no

I repeated this with both nouveau or nvidia-173, unity was not supported on either.

I found the following work arounds:

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GNOME

I was able to run Ubuntu 14.04 with gnome instead of unity.

@tty (Ctrl + Alt + F1):

sudo apt-get update
sudo apt-get install gnome-session-flashback

reboot

@login prompt:

1. Click the image on the upper right of the name


2. Select: GNOME Flashback (Metacity)

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Lubuntu or Xubuntu

An alternative to Unity and GNOME is Lubuntu or Xubuntu.

Just for the record, I did not try either of these since I was able to run Ubuntu with gnome.

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Unity-2d on Ubuntu 14.04?

In Ubuntu 12.04, I remember running Unity-2d because I was not able to run unity. In Ubuntu 12.04, we were able to select Unity-2d at the login screen similar to the way that gnome is selected in the text above.

I was able to install unity-2d @ a tty: sudo apt-get install unity-2d However, I was not able switch from unity to unity-2d. I read some place that unity defaults to unity-2d when it can not run, apparently that did not work in my case.