Need help from someone thats good at linux. I messed up :(

So basically, i installed Linux (Ubuntu Gnome, to be exact) on my Imac, since my Imac is 5 years old and started to work a bit slow running OS X. However, after using ubuntu gnome for around a week and mostly enjoying it, i noticed that youtube was having some very noticeable frame-issues. So with my limited knowledge of linux, i thought maybe it was because my graphics driver wasnt properly installed. So i followed some guides online, some of them involving pasteing commands in the terminal.

Long story short, i pasted a command, screen went black, and now i can't acess a graphical UI. I will show you guys what i CAN access, though:

I would REALLY appreciate some help with this issue, guys. It seems it is a software issue (at least i hope so.)

What was the command you used before this happen? Also, what drivers were you using, and if you tried loading different ones, which were they?

Yeah, give us as much detail as possible, what guide? what commands? What graphics card do you have?

Believe me, i've been trying to find it. All i can tell you is i was basically googling "how to check if graphic drivers are installed ubuntu ATI Radeon HD 4670 graphics" you know, something along those lines. I will keep looking, and will let you know if i find a similar command.

As i mentioned, its a 2009 late Imac. The graphics chip is "ATI Radeon HD 4670". I will let you know if i find the guide or command, but i cant remember the exact location

Get into the root prompt and give us the output of "dmesg" and "lspci". You can find the command you used from the root prompt by doing "tail $(YOUR_HOME_DIR)/.bash_history" or something like that (remember, don't type that literally, write out your full home dir.)

hmm, interesting. Lemme try.. will let you know how it pans out

Just remember that a root shell is very dangerous, there are no warnings, and somethings don't have an undo, if you mess up, you might end up having to reinstall your system.

Also, it might actually be safer if you can ssh into your machine. Do you know if you enabled sshd?

Result of "dmesg"

Result of "lspci"

I can't remember the exact name of my home dir, unfortunately. Is there a command to check it, or something like that? By the way, having to reinstall the OS would be fine, i dont have anything valuable on there at the moment. I doubt it will let me do that, though

edit: i think the command that fucked me over was something like:




What driver did you install? Can you post the guide you followed?

I can't guarantee you that it was this, but it's starting to look a lot like it..

The guide i most likely followed

So basically, i used one of those commands, and my linux peaced out. Screen went "black", as in backlit, but still black display

Okay, you don't know about pastebin. We'd need to see the entire dmesg to be of any help, but I suppose theres no easy way for you to post it to pastebin, and I meant to ask for "lspci -k |grep VGA -A 3". You're gonna look for home at /home/(YOUR_USER). User's home directories go it /home or /users typically. I'm guessing you're espen? /home/espen might be it if that's the case.

I'd say look for that last command so you know what you did to mess up, and just reinstall. I think it might be asking for too much of you to get the dmesg somewhere where we could see it in its entirety.

Edit: I saw the link and what you added to your last post, why don't you try setting it back the way it was before then?

Uh, write what was there before. Are you asking which commands to use? Use nano (PATH_TO_FILE_TO_EDIT).

And what file would that be? Sorry if the anwer is obvious. I was just pasteing a few commands in the terminal to try and fix some youtube stuttering, its not like i'm experienced with terminal

Jaja, sorry you. I'm trying not to give you the answers directly. Well the file in the article is /etc/default/grub. You'll want to allow kms (kernel mode setting) again by taking GRUB_CMDLINE_LINUX="nomodeset" and changing to GRUB_CMDLINE_LINUX="". That should be it iirc.

Also: you shouldn't be so embarrassed that you delete you comment. You're learning, and it's good that you're asking questions, even if they seem obvious to other people.

I only deleted my comment because i thought i placed it in the wrong place. Just removed it to avoid confusion. So, can i please get a step by step on how to change GRUB_CMDLINE_LINUX="nomodeset" to GRUB_CMDLINE_LINUX=""

explain it to me like if i'm 5 years old, i think that is the best approach when it comes to me and command lines

Use nano. nano /etc/default/grub. That will change your prompt so that you're in an editor environment. From there, every thing should be the same as if you were in notepad, or gedit, et cetera. Just remove "nomodeset" from the line you added it to by backspacing.

A professor of mine in school always used to say, "answers are crutches." Especially in computer science (he's a chemist, not a cs teacher.) Telling you to use nano (THE_NAME_OF_THE_FILE_YOU_WANNA_EDIT) as opposed to nano /etc/default/grub gives you the idea that commands are not a compound structure. It's the reason that so many newbies think learning command line is so difficult, if you don't take it apart and show that's a sum of many commonly used parts, it seems like there's a separate command for everything under the sun. Once you start to see how it works, you can use things like lspci -k |grep AUDIO -A 3, and zcat /proc/config.gz |grep CONFIG_TUN, and cat /boot/config-3.19.8 > ./.config and see the how they relate to each other. It's like how chords are made up of only twelve distinct notes, but by making combinations, you end up with more chords, scales, modes, consonances, and dissonances than you can count.

Never mind, im dumb. Here:

so, its set to GRUB_CMDLINE_LINUX="" as you can see. does this only apply to recovery mode or would it look the same in normal boot mode? From some googling i learned (correct me if i'm wrong) that the command i used is for running ubuntu without a monitor, or something like that

That should do it for the whole system.

You mean turning off kms (using "nomodeset")? Or turning it back on again (deleting "nomodeset")? It's used for certain graphics drivers, so yes maybe, it might be for running headless (no monitor), but I think one should disable things in the kernel if he's doing that.

You aren't dumb for expanding your knowledge of technology. I was the same at one point. When you are done auditing grubs configuration file always run 'update-grub' with root permissions.