Change boot mode to legacy

Hi, 

No, it’s not possible, you would have to reinstall Windows if you change the Boot mode. If you wipe the entire drive, you would need the Windows recovery media that you may have received with your system, either in the form of a disk or a USB thumb drive. 

You did not mention which Alienware that you have.    Usually one changes to Legacy Boot Mode in the EFI/BIOS  (actually it is EFI, which takes the place of what BIOS did, but with some changes)  

What are you trying to accomplish?  I have booted Linux Live CD on my Alienware 14, in both Windows 8.1 Pro and Windows 10 Pro. 

It is different with Windows 10.   One must go into EFI and (F2 button) at start, and turn off fast boot.  Then go into Windows 10 Power and go into the Power Mode to tell it to explicitly shut down.   A natural feature of Windows 10 is to place the hard drive (and I guess SSD) into Hibernate mode.   It must be turned off to boot something else. 

Then one can go back into EFI/BIOS, and fiddle with the boot settings, turning off Secure Boot.   Well, it has things it will accept in one order of the other.   Then turn on Legacy Boot.  

But this depends on what you are trying to do.   What are you trying to Boot up?

I have a new Alienware X51 R3 which does not have an optical drive, and no usb came in the box, so, what can I do?

I'm trying to dual boot Ubuntu and Windows 10. I know how to change modes, disable Secuer Boot and make dual boot installations since I've been doing it for years, including in the X51 R2 machine. But in the R3 it seems it's a bit different. The Ubuntu installation seen to complete correctly,  but GRUB does not show up in the next reboot.

I've asked in the Ubuntu forums, and it seems it could have to do with the new m.2 drive, but no luck so far getting this to work.

I would not have known when I first replied, that you had a lot more experience with using Linux on a Windows PC than I.   

As I am sure you know, you can get an external Optical Drive.  I bought one from Dell that plugs into the USB port.   I know some computers today ship without USB ports.  Which would require a cable converter, sigh.   Always more money.

I know that Alienware has a policy of Never talking about using another OS other than they one provide.  

I do not know how to use GRUB.   Let alone using GRUB with Alienware.   Windows does not play well with others.   

I can offer some of my experience, my recipe, for starting Linux on my Alienware 14, for what little that is worth to you.  For one thing, my Alienware 14 has an Optical Drive.   I have started several versions of Linux, including Ubuntu using the Optical drive.  My opinion of Ubuntu is that as an OS, it has the same issue as Windows, it is so large, so resource demanding that it demands the latest hardware to be used with it.  My Alienware hardware is sufficient to run Ubuntu.   I am more likely to use one of the versions of Puppy Linux.   FatDog being interesting.  The maintainers reached into their own pocket to buy an EFI code.  I have used some of the other Puppy versions.   Puppy can start using the main processor for video, thereby giving one some breathing room to figure out which video driver to start.    Most versions of Linux seem to choose the wrong video driver for the card in my  Alienware.   I know that Windows 10 has a bunch of disc partitions.   Moreover I have an M-Sata which I am sure that is used by the Windows OS.  It is like a small SSD in front of the Terabyte Hard drive.   I have found I can create a USB key with Linux, from another computer and boot it to my Alienware 14.   USB boots Linux faster than the internal optical disc.  

Ubuntu gave me an error message about the hard drive being "Unstable"  and said a lot I did not understand.   So I powered off computer, and eventually found the part about Windows 10 putting the hard drive in Hibernate mode.   

It is a real pain to go into the EFI/BIOS to switch between OS's.

I was at my local computer store the other day, and they had a sign saying that before they would work on any Windows 8 or Windows 10 Computer that either the owner had to provide the backup discs or USB for that exact machine, as those versions of Windows have a Code that is stored in the firmware.  If one does not have the backup, the technicians will make them for charge before working on the computer.   I ran Belarc to get the 'hidden code' on some of my Windows 10 computers, but I guess I should make Back-Up discs.   Alienware comes with a fledgling program called Respawn to create discs.   Like any program that is meant to do anything, and also sell a better version of itself to us.  It does unexpected things.   In my case, I put all my person files onto an external drive, then I started ReSpawn to get a new copy of Windows onto my Laptop (to use the restore partition on my Alienware).  It insisted it had to back itself up, the only external drive I had, already had my personal files on it, but plenty of space for another entire copy of the hard drive.   So I let it start.   It asked if I wanted everything, to which I said no.   ReSpawn clobbered everything on the hard drive to make an abbreviated copy of my personal files.   I could see I was not supposed to stop the process after I started it, but usually software knows not to delete other things on the hard drive.   Unexpected consequences.   At some time Windows 10 and Respawn will bug you to create back ups.   At this time, I think one can get the Windows 10 ISO from M$.  However it is nicer to have a back up that properly installs all the correct hardware drivers, even though Dell website that makes it easy to find the ones you need, and gives info on which order to install them.   

When I bought my Alienware 14 I wanted to run Linux with a virtual machine inside Windows, which is why I got 16 GB, and the Pro version of Windows to use their Hyper-V.  Avoid all those tricky problems of long boots from optical disc, no more conflicts with video driver.   I had used VMware Fusion on my Mac, which ran beautifully.  I was astounded to find the huge price for the Windows version, I never bought it.    One must look around a lot for the documentation for how to use Hyper-V.  The free virtual machines never worked for me with Windows 8.1 Pro.  

Using the Alienware for Linux has not been very much fun for me.   During the Holidays, I bought a bottom of the line Dell Laptop with Intel 4th Gen, and only an Intel Video Chip.  (it has USB ports, for which I bought the external optical disc drive)  I have started this several times with Linux on USB key.  I have been building the USB Key install on my very old mac.   I was surprised that for such Minimal Hardware, and Windows 10, that it seems to pull everything as fast as the internet can provide.  I do a speed test with WiFi (it only has WiFi) and it tests at fifty Megabytes, the max provided by the Suddenlink in my price ranger.   

Of course, Puppy Linux runs like a 'bat out of ***'  on even old computers that barely creeped along with any version of Windows.   Putting Puppy Linux on an Alienware is so fast it probably will be made illegal some day.  I  use an external mouse to control it better.   I do not like the Symnatics Drivers even on Windows.   

When you discover the recipe to use Linux on your Laptop, then pls post back here.   Also try to find out if the version of Linux you are using will still use the fans for cooling.   

Hi PURPLE397! Thank you for all this information! It's so kind of you. In fact, I'm asking about Ubuntu because it is more likely to find support, but the truth is what I want to install is Elementary OS, an Ubuntu's derivative. It's way lighter and faster, in my opinion, comparable to those distros equipped with  LXDE.

I know Dell is not very Linux friendly, but I know they've released some Ubuntu-based hardware a while ago, for example they sold an Ubuntu flavoured X51 R2 back in 2013.  At least I hoped that my X51 R3 could be compatible with Ubuntu as well. For now, I've got an extra ssd drive to keep my installations separated because it seems way more difficult to dual-boot from only one drive with both OSes.

As it seems EFI support is not fully mature in some distros, I want to change my boot mode to Legacy and try that way, but first I need to figure out how to restore Windows. As my machine did not come with a CD or USB backup drive I think my options are quite limited. I was hoping for someone in Dell could recommend me a solution.

I'll keep you informed if I get this to work. Thank you for your interest.

Hi all! Finally I found a way and I'm now happily dual booting W10 and Elementary OS Freya in UEFI mode.

First of all, I found that nowadays with these new machines, the Windows 10 key comes embedded into the motherboard, so you don't need a key to reinstall. While you install the same version of W10 it came with your pc, you're good to go. You can use an ISO from the microsoft site and you will not be asked for a key through the installation. In any case, you can retrieve your key with the free tool OEM Product Key Tool from Neosmart if you want.

So what I did was to copy the Windows 10 iso to a USB drive using Rufus, and booted it in UEFI mode. From the installer, I wiped all my partitions and installed W10 in the desired one. Everything went smooth. Windows booted as expected. 

After that, I booted a USB drive with Elementary Freya in it (this is valid for any Linux distro) and installed it too as always.

It's important to note here that as my graphic card is a GTX 960, there are some issues with it as well as the 900 series from Nvidia (Maxwell architecture). As they did not release the binary blobs for the open source community to build the nouveau drivers for this card series, you may be wellcomed with a black screen or a -22 error while launching the installer. The solution for me was to switch my HDMI output to the integrated Intel card to prevent the black screen and to edit the boot options in the menu: when you are presented the "Try Elementary OS" and "Install Elementary OS" menu, instead of just selecting the install option, press 'e' over that option and add 'nomodeset' before 'quiet splash' . The press F10 and the installer should be fine.

When the installation is complete, you should install the drivers form nvidia downloading them from the official site. After they're installed, power off the machine and change again the HDMI source to your graphics card. 

Now you have both OS's installed, BUT:

The Alienware will boot Windows 10 anyway, as these are the things that happen with UEFI and W10. I was unable to make it work with GRUB, so I did the following:

- Boot Windows 10, disable Fast boot and, in a command prompt: bcdedit /set {current} recoveryenabled No. This will prevent the bootmanager torecover when changed.

- Disable Secure Boot in your UEFI settings (press F2 when booting your pc to access it)

- We will be using the rEFInd boot manager, so download it an copy it into a USB drive. Boot from that drive in UEFI mode and you should be presented a menu with your two OS's. Select Elementary or Ubuntu or whatever you've installed and let it boot.

-Now, download the rEFInd binary zip files from the website. Use the install-refind binary to install it. This will not be sufficient, at least for me, as Windows keeped booting instead of shoing rEFInd menu. So I had to go through the steps described here, in the section 'Rename filles manually' inside 'Alternative naming option'. Basically you must rename the windows boot manager in the EFI partition and copy inside that directory the rEFInd manager and rename it to the windows manager. 

After this steps, rFEInd manager should be booted when powering your Alienware, and you should be presented with the options to boot Windows 10 and your Linux distro. In my case, Windows 10 was labelled as unknown OS, but when selected it booted correclty.

Hi all! Finally I found a way and I'm now happily dual booting W10 and Elementary OS Freya in UEFI mode.

Thanks for taking the time to post this solution. Good work.