Cannot boot 14.04 Ubuntu

Solution 1:

I had similar problems with installing Ubuntu on my new Lenovo W540 portable workstation (also a dual-boot setup). I tried installing 15.04, 14.04, and 14.04.2 -- both amd64 and x86 versions with to avail. While I've been using Ubuntu for about two years now I'm still rather n00b in the under-the-hood side and felt that I was not getting ahead with resolving my problem. Until I found this question, that is.

What Mitch pointed to ended up solving my problem. Well, this problem anyways (more at the bottom about my new, possibly related issues). From the link he provided I found my way to Ubuntu Help's BootOptions page that detailed (clearly enough) how to set the acpi=off parameter when booting the liveCD.

To detail the steps that I did:

1. Booted with LiveCD on DVD. I had tried both DVD and USB before but used a DVD this time around as some have reported that they've been able to install from DVD when they've had problems with installing from or even launching the Live version from USB. I don't know if it mattered that I used DVD vs. USB, though.
2. Once the DVD kicked in I essentially followed the steps detailed starting at "Ubuntu CD Advanced Welcome Page Options" in the above-linked BootOptions page and set the parameter acpi=off as part of that (via pressing F6 in the Advanced options screen). FYI, I pressed the Esc key "when the small logo appears at the bottom of your screen". The instructions note that any key should work.
3. I chose to "Try Ubuntu without installing", going into the Live version and then
4. Installed Ubuntu from the live desktop (Install now, or what ever the icon is on the desktop there) as some have reported that they were able to install via the Live option when the direct installation didn't work. As with DVD vs. USB, I don't know if that mattered.

That's really it. The installation (with acpi=off) didn't run into any irregular issues of any kind. Now, I'm not sure but I think I chose to also install both updates and third-party applications in the installation options. Some have noted that not selecting these have helped in problematic installations. You might want to try without if you have issues.

Now, I should add that while the first boot to Ubuntu after the installation was completely normal I ran into a halt on my second boot to Ubuntu after I had installed the first detected batch of updates (in my case about 180MB, IIRC). I can't remember for sure if the system stalled/froze when powering down or when powering up, unfortunately. Anyways, I was able to resolve that halt by adding the acpi=off kernel parameter in the Grub options as detailed (again, clearly enough) in the question that Mitch linked to above (in the Chosen Answer to the question answered by izx).

I should finally add that while the installation seems to have gone through fine I did run into two new issues.

1. I am now having persisent issues with the system not being able to power off or reboot (in Ubuntu, all ok in Windoze side). I have to brute-force with the power button. This might be also related to the acpi/APIC parameter per reading various people's problems with some kernel/hardware combinations and powerdown/reboot problems. The problems seems to have been around for years with varying combinations of kernel version(s) and hardware. (I don't have sufficient rights to post more links here but you can find these by searching with acpi / APIC / ubuntu power down, etc search terms). But so, just so you know that powerdown and reboot freezes might be next issue you may be facing, which are not show-stoppers, though, as you can still use the system -- just need to brute force power off from power button.
2. For some reason after the installation was done and I booted into my fresh Ubuntu (15.04) installation neither the keyboard nor the mousepad of my laptop work anymore. They work ok up until the Grub2 screen. After that, no more. In my case I'm able to use the computer normally with a wireless USB-dongle keyboard & mouse.

I don't have a solution for neither one of the two new problems as is.

I hope the installation solution that worked for me helps you too.