I was using 2 OSs, Windows 7—installed on C:—and Ubuntu—on a 60 GB partition next to G:.

Now, I changed the processor and motherboard and reinstalled Windows. Ubuntu was left untouched. When I start my PC, I’m missing the option to choose between Windows and Ubuntu.

I understand that on installing a new processor, I need to reinstall the OS.

I’m not able to get access to that 60 GB partition next to my G: drive so that I can format it! I went to Disk Management in Computer Management and I found the 60 GB partition. When I hover the cursor over it, it just shows “Healthy (primary partition)”. On right clicking, everything but the “Delete” option is grayed out—including the “Format” option! I want to reclaim those 60 GB.

  • 1
    Your missing an option to switch between Windows and Ubuntu because you reinstalled Windows. You need to repair the GRUB bootloader. Its not clear what you actually did. Your descriptive of what you did isn't clear enough. – Ramhound Mar 17 '15 at 18:27
  • You can't "format" the 60GB Ubuntu partition because it's a partition type that Windows doesn't recognize, so Windows can only "delete" it. So delete it and create a new 60GB partition with Windows, then format it. ;) – Ƭᴇcʜιᴇ007 Mar 17 '15 at 18:35

You don’t need to reinstall your operating system when you change your CPU.

If you want that space back and Windows refuses to work with it directly, just delete and re-create it. You should then be able to use it normally. If not, please provide a screenshot of Disk Management.

So, now that I rewrote the question, a little more specifically: When upgrading your motherboard, reinstalling Windows is indeed encouraged, but no longer necessary in most cases.

The Ubuntu boot menu is missing because Windows overwrote it when you reinstalled it. Ubuntu offers a wiki page specifically for this case: Recovering Ubuntu after installing Windows. I won’t copy this information because it’s likely to change in the future.

  • Related SU question: I can't boot to Ubuntu after installing Windows 7 – Ƭᴇcʜιᴇ007 Mar 17 '15 at 18:32
  • I'm not able to add pictures. Requires 10 rep points. I've just got 3. I'm completely new here you see. And yes, I changed my mobo too-not just the processor. I haven't tried recovering Ubuntu through a CD as yet. I'll try that. Lastly, can you tell me what happens if I use the "Delete" option on a partition in the disk manager? – Vimugdh Lall Mar 17 '15 at 19:19
  • @VimugdhLall You don’t have to embed them. ;) What happens? Nothing much. It just removes the entry from the partition table. In Disk Management, it turns into free space (colored black), in which you can create a new partition or extend the preceding partition. – Daniel B Mar 17 '15 at 20:03
  • Thanx a tonne @DanielB I turned that partition to free space and recovered that memory. Will re-install Ubuntu now. – Vimugdh Lall Mar 18 '15 at 17:11

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.