I recently purchased Dell Inspiron 5548. 64bit System, 8GB Ram, 2GB ATI Graphics Card It came with Windows 8.1 Single Language Edition.

I completely removed the Windows, also formatted the recovery drives. So now I have a Fully Empty 1TB Hard Disk.

For now I want to install only Ubuntu as single OS not dual boot. Can I add Windows 8.1 in future on this system without removing current installation. (Chances of me using Ubuntu is almost zero but still asking as curiosity)

I want partition the disk into 3 GPT partitions as following:

1) 100GB Partition fro Ubuntu 14.04 64bit OS. 2) 100GB Partition for Storing Books etc and 3) 800GB Partition for Media Storage like Songs, Movies etc 4) 16GB as Swap and 5) may be 500MB to 1GB for EFI Partition if needed.

So how can I install Ubuntu 14.04 on this EFI System?

If I disable EFI and use Legacy mode, does it affect my performance?

If Yes how can install Ubuntu with EFI Enabled? I'm quite new to this EFI term, so please explain in detail.

I tried installing with EFI ON before writing this question, but got ERROR Message saying "Unable to mount vfat EFI partition". (Installation windows said I need to create on partition at least of 35MB or more of type EFI, so I created of 1GB of ext4 and set it as a EFI partition but got above error message).

Please Help ASAP as I have no other OS my system and unable to use it.


You can install Ubuntu as a single system. It must not be hard. Use a 64-bit Ubuntu release. Boot from liveCD, start gparted and create partitions you need.

If you disable EFI, it won't affect performance, but the system may boot a little bit slower.

EFI partition should be not less that 50 MB and formatted to fat32. In most cases there is no need to make it larger than 200-300 MB. I use 100 MB size and never had any problems.

But there are issues discussed in the net, that some EFI's deal incorrectly with partitions smaller than 512 MiB. So to be 100% safe you can create a 550MiB EFI partition.

Also 32 GB swap is an overkill for 8 GB RAM. I suggest making swap not more than 4 GB. In 99% it will not be needed at all. Hibernation is also not useful for this amount of RAM. System will boot as fast as thaw.

When you install Ubuntu just set EFI partition as EFI boot, or /boot/efi, I do not remember the exact name in the installer. But you will easily find it from a drop down menu.

Everything else should be as before, like installing without UEFI.

You get this error, because you formatted EFI partition to ext4, not to fat32.

You can install Windows 8 later, but you will need to re-install grub after that. Boot repair is a nice utility for that.

  • I agree with this answer, except that some EFIs have problems with FAT32 partitions smaller than 512MiB. Reports of such problems are on the Internet, but I don't happen to have a URL handy. Because of the possibility of MB-vs-MiB confusion and because mkdosfs switches from 16- to 32-bits at an odd place, I generally recommend making an ESP at least 550MiB in size. Note that the difference between a 200MiB and 550MiB ESP is puny compared to a 1TB disk's total capacity, so wasted space is not an issue. – Rod Smith May 28 '15 at 13:30
  • OK, I will edit. – Pilot6 May 28 '15 at 13:31
  • But after installation when I start Laptop Ubuntu show message "Graphics Not Detected" and show message to run it in low resolution mode. Ubuntu works fine on Live USB. I have ATI Radeon M265 2GB Graphics + Interl HD onboard graphics. – CrownedEagle May 28 '15 at 13:45
  • This is not connected to UEFI. You need to install AMD proprietary driver. Ask another question or search for a solution. There are plenty of them. – Pilot6 May 28 '15 at 13:47
  • But do not download it from AMD site. – Pilot6 May 28 '15 at 13:52

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.