Q:

Ubuntu Gnome freezing during startup

This morning I installed Ubuntu Gnome 15.04.  I installed a few applications and restarted the computer a couple times without issue.  I just ran updates though, and when I restarted the computer after updates were finished, the computer hangs at the splash screen with all three dots filled.  
Ctrl+Shift+Num Keys does nothing, same with Ctrl+Alt+Del.  
The only thing that works to make the computer do something is pressing the power button.  The screen will flash the output text from startup.  The last two things I see are:
Starting GNOME Display Manager
gdm.service

The text flashes, then it goes back to the splash screen, no longer frozen, then the computer shuts down.  I am able to boot from the linux usb drive that I used to install Ubuntu, but am not sure which logs to look at or how to move forward.
UPDATE:
Found the boot.log file these are the last few entries:
[[32m  OK  [0m] Started Restore Sound Card State.
[[32m  OK  [0m] Started Permit User Sessions.
[[32m  OK  [0m] Started LSB: Set the CPU Frequency Scaling governor to "ondemand".
[[32m  OK  [0m] Started LSB: Speech Dispatcher.
[[32m  OK  [0m] Started Restore /etc/resolv.conf if the system crashed before the ppp link was shut down..
[[32m  OK  [0m] Started Console System Startup Logging.
[[32m  OK  [0m] Started Ubuntu live CD installer.
[[32m  OK  [0m] Started LSB: daemon to balance interrupts for SMP systems.
[[32m  OK  [0m] Started D-Bus System Message Bus.
[[32m  OK  [0m] Started Avahi mDNS/DNS-SD Stack.
[[32m  OK  [0m] Started Bluetooth service.
[[32m  OK  [0m] Started LSB: automatic crash report generation.
[[32m  OK  [0m] Started LSB: Record successful boot for GRUB.
[[32m  OK  [0m] Started System Logging Service.
[[32m  OK  [0m] Reached target Bluetooth.
[[32m  OK  [0m] Started Make remote CUPS printers available locally.
         Starting Make remote CUPS printers available locally...
[[32m  OK  [0m] Started Login Service.
         Starting Authenticate and Authorize Users to Run Privileged Tasks...
[[32m  OK  [0m] Started Authenticate and Authorize Users to Run Privileged Tasks.
[[32m  OK  [0m] Started Accounts Service.
[[32m  OK  [0m] Started Modem Manager.
[[32m  OK  [0m] Started Network Manager.
[[32m  OK  [0m] Reached target Network.
         Starting /etc/rc.local Compatibility...
         Starting MySQL Community Server...
         Starting Network Manager Wait Online...
[[32m  OK  [0m] Started /etc/rc.local Compatibility.
         Starting Wait for Plymouth Boot Screen to Quit...
         Starting WPA supplicant...
[[32m  OK  [0m] Started WPA supplicant.
[[32m  OK  [0m] Started Detect the available GPUs and deal with any system changes.
         Starting GNOME Display Manager...
[[32m  OK  [0m] Started GNOME Display Manager.

If I start in recovery mode, it gives me options for recover, I select continue boot.  I receive a message saying that some display manager won't work after recovery boot, that a restart might be necessary.  I say continue, then it freezes at a blank screen.  I push the power button once, it flashes to a terminal with login prompt and then restarts.
I've also tried going into recovery mode and repairing packages with no luck.

A:

Maybe related with this bug? 
https://bugs.launchpad.net/ubuntu-gnome/+bug/1460045
I've got that issue with Ubuntu Gnome 15.04 after upgrading to Gnome 3.16 (in 3.14 version my laptop works ok).
Hope it helps

