Unable to boot ubuntu in a dual boot with windows 7 on Lenovo L420
 

Hi all,
I recently installed ubuntu 11.04 on my Lenovo L420 which was having windows 7 already installed.The system is partioned into 4 drives,C,D,E,F.Windows is installed on C drive and ubuntu on D drive.However when I boot into ubuntu I get a screen of black and white horizontal lines instead of the login screen.Windows is working fine.Is it an installation problem or something else?

System configration:
4 gb ram,500 gb hard disk,intel i3 processor

Did you install Ubuntu on its own partition, not a wubi install?
Which bootloader are you using to boot? Windows? Ubuntu Grub2?
Do you get the black/white lines after selecting Ubuntu from whichever bootloader menu you are using?

It's probably a video driver problem.

Are you able to get a command line?

Wayne Sallee
Wayne@WayneSallee.com

@yanceck:its not a wubi installation.Ubuntu was separately installed on the other drive.Yes I get the black and white lines after selecting which bootloader to use and when ubuntu is selected.Ubuntu is the default OS.

@wayne sallee:I am not able to get the command line also.i tried using alt+ctrl+F3,but its not working.if its a video driver problem how to correct it?

---------- Post added 08-24-11 at 09:12 AM ----------

@yanceck:grub is the bootloader

Try alt+ctrl+F1

You can edit /etc/X11/xorg.conf and set it to a vesa driver or xorg driver, or some other simple driver. Check with Ubuntu to see what drivers they include, and if they have software that makes it easier to update xorg.conf with simpler driver.

What graphics card do you have?

Wayne Sallee
Wayne@WayneSallee.com

i had installed 32 bit version of ubuntu 11.04 on my 64 bit machine.could that have been a problem?

There is no problem in installing a 32 bit version on a 64 bit machine.
Just don't try to install a 64 bit version on a 32 bit machine. :-)

Wayne Sallee
Wayne@WayneSallee.com

I suggest you install one of the many free virtual machine applications. It makes testing and using linux as easy and safe as can be. Your system would be able to run a VM close to or above native speeds.

hello, i own a thinkpad x220, and originally, it came with several different windows partitions, which made it hard because of the 4 primary partition limit. in windows, login as an admin, open the windows menu, and in the text box type, 'partition' and open the partition program, and just look to see if it senses your ubuntu partition. alternativley, you can use gpart, a great live cd, to do the same thing

Live-cd...

Download a copy of PartedMagic or some other live-cd that will boot, open a terminal, and use the command, with root privileges, "fdisk -l" to read your partition table. Compare the results with what the Windows 7 partitioning tool reports and try to understand what you have installed and where.

As mentioned, there is a limit of four primary partitions, so unless you installed linux within Windows, you have used at least one partition for linux. linux does not label partitions as does Windows, so to do any repair of your GRUB installation, you need to be able to list the partitions according to GRUB's satisfaction. For GRUB, the first partition is listed as 0, the second as 1, etc.

However, since you get as far as a Ubuntu splash screen, Ubuntu seems to be loading, but as mentioned by Wayne, has a problem with your graphics hardware. Can you boot Ubuntu as a live-cd? What is your graphics hardware, and as Wayne asks, what happens if you specify a particular driver for it to boot (vesa, nv, etc.)? Try this out with your Ubuntu live-cd with a cheatcode.

For my experience, anytime grub does not work well on multiboot system, just it is a bit "complex" to use, therefore may be a good solution to use the "old" but always good working lilo bootloader, together with windows boot manager; during installation process, select to install lilo on root partition (e.g. hda3) then boot windows and install BOOTPART utility:

http://www.winimage.com/bootpart.htm

Just type bootpart and all partitions are listed, then select which you want to add to windows bootmanager; make a reboot and select your linux partition, in few seconds you are your linux system ready for you ;-)