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I'm brand new to Linux/Ubuntu, and I have multiple flash drives with the latest release on it. Last night, I mistakenly installed the 32-bit OS while I intended to install the 64 bit. Just before doing so, I took an image of Windows 7 64 in case something went wrong.

I want to upgrade to 64 bit version of Ubuntu while keeping W7 64. Is there a way for me to easily do this? If I use my 64 bit live disk, will the 64 bit version overwrite the 32 bit?

Alternatively, could I just recover the PC from the image I took before installing Ubuntu, wiping everything clean INCLUDING 32-bit Ubuntu (then install 64)? Or will the W7 recovery ignore Ubuntu all together?

Thanks All!

marked as duplicate by Mitch, user117103, mikewhatever, TrailRider, Seth Feb 2 '14 at 21:52

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  • There is a question here about the differences between 32bit and 64bit... The 32bit OS should be fine with more than 3GB of RAM, due to the default PAE kernel. Apart from that, unless you do number-crunching, there is not much difference in speed between the two (thought 64bit can use more memory), so you might not need to reinstall. Is this a dual boot with Windows? and what is the output of uname -mpir? – Wilf Jan 31 '14 at 15:19
  • The 32 bit does work quite well, but it's not seeing the 6 gb of RAM, so I'd like to utilize that. Thanks for the response! – candlepinfrank Jan 31 '14 at 15:50
  • Also take a look at askubuntu.com/questions/291994/… – Mitch Jan 31 '14 at 16:32
  • don't drink and upgrade – Jonesopolis Jan 31 '14 at 20:16

Yes, if you attempt to install the 64 bit image it should give you the option to overwrite the 32 bit one. If memory serves me correctly, it is pretty friendly and you get presented with the option to keep windows and overwrite the ubuntu installation. But if not, you can just choose the linux partition to overwrite.

Personally I would avoid recovering the whole PC if you can help it. This sounds like a "nuclear" last resort kind of thing to do if you screw up somehow and blow the windows partition away altogether.

  • That's good to know! Do you know if this will affect the dual-boot in a negative way? I'd hate to mess with the GRUB launcher. – candlepinfrank Jan 31 '14 at 15:51
  • it should redo the GRUB launcher so if it works ok with your 32 bit install it should work the same way after the re-install. I would just go ahead and stick the 64 bit live CD and see how far you get (it's v obvious when you have to choose an option that is destructive). If it all looks good then just go ahead; if you get a confusing option then update this question or ask another. – TooTone Jan 31 '14 at 15:56

Are the two of operating systems in the same drive ?

If not you can remove the Ubuntu (maybe by formatting the drive) and then install a fresh 64 bit; In this way you will probably lose the booting options which can be recovered by repairing the grub:

How can I repair grub? (How to get Ubuntu back after installing Windows?)

  • They are on the same drive, yes. Probably should not have done that. I think I will be trying to install the 64 version and just see how it goes by overwriting. – candlepinfrank Jan 31 '14 at 16:09

Best to use Something Else or manual install.

Choose existing / (root) partition, format ext4.

Same for /home if separate partition, if you have any data in /home DO NOT check format on it.

It should find existing swap.

Reinstall says overwrite Ubuntu but it also erases existing Windows.



You can install Ubuntu64bit above Ubuntu32bit while keeping your documents by following the following procedure of the Community Ubuntu Documentation: https://help.ubuntu.com/community/UbuntuReinstallation

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