Hello, first of all I have to say that I am rather aLinux newbie.
Now, let's get straight to my problem:
I am running Xubuntu LTS 14.04 on a Laptop. I have to say that it was very unstable anyways, because it frequently crashed without any reason (e.g. every time, I ran "lspci" it crashed after successfully executing it), but that is nothing to the disaster that happened to me now: I was installing CUDA from Nvidia and nothing seemed to be wrong until it (successfully) completed "sudo apt-get install cuda". It still printed out my username, meaning that I should be able to type in the next command, but instead it crashed... When I rebooted and chose the Ubuntu item in grub, instead of booting Xubuntu it said: "Couldn't load initrd".
Now, since I am a newbie, I was horribly shocked and therefore ask here for help. What does this error mean and most importantly How do I fix it? Thank you in advance!

Did you follow the process explained at the link below?

http://askubuntu.com/questions/53342...n-ubuntu-14-04

All that crashing and now initrd not loading points to hardware problems, possibly dying hard drive.

Welcome to LQ!

I am not an Xubuntu user (or any 'Buntu's) so I cannot offer specific advice.

But I will offer the following comments that will help you get better answers from others.

First of all, can you be a lot more specific about just how "it was very unstable anyways, because it frequently crashed without any reason". "Crash" may be a technical term applicable to other OSs, but you need to be a little more specific here.

Instability and unexplained behavior can often indicate hardware issues, memory failures, disk corruption or failure, loose cables, etc., etc... Those need to be investigated before attempting software fixes.

It is also possible that you have installed incorrect library or other software versions that cause problems. Only you can know the previous history and condition of the system, so a bit more info there would help as well.

And whether or not the original problems were hardware or software related, they need to be solved before trying to troubleshoot installation of some new software, otherwise you are simply disappearing further down the rabbit hole...

So, please provide a more complete description of the original instability problems, some hardware info such as RAM, CPU, the output of lspci, etc. etc., and some info on the history of the installed system.

Good luck!

1 members found this post helpful.

No, because the link doesn't describe my problem.
You see the guy in the link had already a previous version of Cuda installed, I didn't. My problem is completely different, I must have described it unproperly. I don't even have a Terminal at hand, my Linux doesn't boot AT ALL. I don't know what to do to fix it. The guy in the link is already talking about post-installation things, but I am not there. My problem is that Xubuntu crashed immediately after the command install cuda.
Now it says something about that it couldn't find initrd when booting

First of all thank you for all the answers
The hard drive - or rather the SSD - seems to be normally working.
I have a dual boot with Windows, and Windows never crashed in the entire life of the Laptop (!)

@astrogeek
Ok, here is some info:
The Laptop is not even half a year old, it's a Lenovo y50-70:
Cpu: Intel i7 4720 HQ (2.6 - 3.6 GHz)
Ram: 8 GB DDR 3
Gpu: GTX 960M 4GB GDDR5
Storage: 250 GB SSD

I installed Xubuntu LTS 14.04 only using the default partition scheme, 8 GB swap and the rest for one partition with everything else. As I said, I dual-boot Windows 10 and Windows works like a charm. But I already had huge start problems with Xubuntu: The WLAN wasn't working out of the box (Broadcom) and I had to manually install drivers. Everything else worked out of the box hardware-wise. But again, Linux seemed to be unstable. Besides of the lspci crash, the system also crashed when I wanted to shutdown without closing all applications first, or it also sometimes crashed when I turned off the screen, made a break and when I came back 10 minutes later, it crashed. There are also some other random crashes, that I couldn't sort into a specific pattern.
The crashes all were the same: The screen froze. I can toggle whether the screen is on by pressing Fn + F2, which even works in grub, but on the crash even that didn't work. Also the fans were going louder and louder after the crash, maybe the CPU was going full 3.6 GHz after crash, or maybe it was just for safety.
I installed only a few things, like Java, Sublime Text or LaTeX (TeX Live).
I hope that is enough information. If you need any other information, I am happy to provide them
Btw. If nothing else helps, I might even do a cleaninstall of another distro. I didn't like Xubuntu that much either and my Laptop is not in need of running only lightweight things.

Thanks, that should be helpful.

It is possible that your first install was corrupted somehow. Did you verify the checksum on the downloaded DVD/USB installer image?

If you do not have anything on it that can't be overwritten yet, it might be easiest to just perform another install. Especially if you want to try another distro anyway. If you do, be sure to verify the checksum of the install media and be sure to download from the project's home instead of third party sources.

1 members found this post helpful.

I didn't check the ckecksum
The problem is, that I do have files in my home directory, that must not be deleted... Is there any way, how I can backup those files before the cleaninstall?
Also what do I need to pay attention to, when I do the cleaninstall? For example, what do I need to do to remove the "Ubuntu" entry from grub? Also, is it safe to just install over the old 2 partitions?
Btw.: I am looking for another distribution right now... What do you think of Fedora w/ KDE?

Sorry for slow reply.

There are several ways to get files off that partition before you reinstall, some might be easier than others.

If Ubuntu will boot to normal or single user mode, you can transfer them over over the network to another machine or save them to a USB thumb drive. Depending on the size and number of files you migh just email them to yourself.

If it does not boot at all then you might boot to a live DVD, mount the partition and transfer them that way.

A slightly more complex way, but still easy enough, you could boot to a rescue or utility disc (GParted is a favorite of mine), format the swap partition as a linux partition and write the data from the root partition to the newly formatted one. Then when you reinstall only reformat the root partition and install without swap or create a new swap partition, then recover your data from reformatted original swap. Might sound like a lot of effort but really it isn't.

As far as Fedora... I don't really have an opinion. I am a die hard Slackware user and just don't have much exposure to other distros from a user perspective. I see a lot of good comments for Mint as an easy to install and use distro.

And of course Slackware - not for everyone, but not difficult in any sense. It requires a little more knowledge and effort from the user to make it just what you want, but that makes it the perfect distro for a lot of people... might be worth a quick look!

1 members found this post helpful.

I would suggest you definitely do an md5 checksum on the iso. I don't use windows but doing an online search on how to do it on windows 10 should get you some results. Boot your new installation DVD or flash drive and mount the partition on which you have the files and copy them to another drive.

If you install another distribution it will overwrite the grub entry for Xubuntu so not a problem. Yes you can use the partitions you used for Xubuntu, just make sure you get your data off the drive first and select to format the partition(s) during the install. If you are using windows 10 on this computer, are you using UEFI? Some information on this at the link below specific to Ubuntu and derivatives but much of the info will apply to any Linux install. UEFI and MBR installs don't mix so you need both the same.

https://help.ubuntu.com/community/UEFI

2 members found this post helpful.

Thanks for the detailed answers!
I changed my mind, and I am gonna try Kubuntu now instead of Fedora, because I realized that it was more the GUI that I disliked than the system behind the scenes.
I also am trying the latest build instead of LTS now, maybe this maximizes my chance to make Linux detect all hardware right away. I already downloaded the Kubuntu image, but I didn't do a md5 check, but a SHA 128 check, and it was the correct checksum (I don't understand how a download can be corrupted to change the hash without corrupting the whole download, but anyways it is fine now)
I have to wait to get a new USB stick so I cannot make the reinstall right away, but I will report if it worked when I got one (probably in a few days)
Yes, Windows is installed in UEFI and the partitions are GPT.
Thank you for the link.
In the link it says something about an extra UEFI partition, but I don't have such a thing in my Xubuntu installation, although I definitely installed it with the automatic installer. Could this be the problem to my instability? And if so what could have caused it?
Also the start of my Linux partitions have an offset of >100 GB from the beginning of my SSD, is this a problem?

If you installed Xubuntu in UEFI, you should see it's files in the EFI partition along with the windows EFI files. I believe they would be the files listed below and probably named ubuntu.

I just realized, I can boot previous versions from Xubuntu under advanced options in grub and I do see this Efi directory when I boot a previous version. I somehow also managed to get into the uptodate Xubuntu without crashing, but it says that it couldn't load /boot/efi upon booting and asks me if I want to skip or repair manually. When I press skip, I am in Xubuntu and can use a terminal. If I go to /boot/efi, the directory is empty. Note that it wasn't empty, if I navigated to that location in an old version from Xubuntu.

Ok, I actually already got the USB now and tried out both Kubuntu and Fedora and they both don't work either - even as Live Image. Luckily, I got from those distros more information about the problem than from Xubuntu:
Kubuntu gives the option to check the disk for defects in grub as an extra entry. I did this and at the end it said that it found errors in 2 files, but no more detailed information! Photo
And when I tried starting Fedora, this error occurred:
Photo
Also, I was able to sometimes boot into the Kubuntu Live Image, but it crashed so randomly and frequently that it was even more unstable than my Xubuntu. And Fedora was similar. Can you extract any new solutions for my problem from the new data?

Ok, I finally found a solution!
I had to type "nouveau.modeset=0" before booting to make it work. (So it was something with the graphics drivers) Now I got a stable Kubuntu installed (at least it is stable for now). Thank you all for your help!
I just got one final question: When I had the live image running, it listed some drivers in the drivers menu. Now that it is installed, there is no proprietary driver listed. What is the fastest way to get those drivers again? This is important, because now I don't have a WLAN driver and therefore no internet. Also, is there any command that I should run before installing new software?
Should I run apt-get update when I have internet?