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Converting from BIOS to UEFI

Converting from BIOS to UEFI
« on: November 14, 2017, 08:39:46 am »
Hi

I have a Z79P-D3 Mobo and currently I am using the BIOS section with hard drives formatted to MBR. However, I am now looking into converting to UEFI but I'm somewhat confused as to what Mobo settings I need to change in order to achieve this. I would appreciate it if someone could give me some guidance on what I need to do to run with UEFI and GPT disks. I believe it involves making changes to the Windows 8 Features section of the UEFI firmware but what changes are needed? Any help would be much appreciated.

Thanks
Tracey

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Re: Converting from BIOS to UEFI
« Reply #1 on: November 15, 2017, 07:11:24 am »
Hello Tracey,
Its not possible to convert your install from MBR to GPT (easily) simply by making some changes in BIOS.  The formatting on the disk has to be changed as well.  To save your current install and OS, I would suggest using Macruim Reflect or Acronis True Image. 

I have used Macrium for this several times, converting an MBR install to GPT so bitlocker could be enabled.  This is a helpful article:

https://kb.macrium.com/KnowledgebaseArticle50151.aspx

One of the other benefits of Macrium is its automatic FixBoot utility that is built into the software.  It moves and repairs what gets broken during the restore and takes out all of the guess work..  The easiest way to do this is to have a usb hard drive and a USB stick with your OS.

You partition the hard drive with a small winPE boot partition and a second large partition to store your back up image.

You boot into Macrium with the PE environment hard drive, run the program and back up your system disk (to the large partition).  This way you have Macrium and your saved disk image in one location.  Shutdown.  Now you change your BIOS settings from Legacy to UEFI.  Then use your USB stick with your OS to convert your system drive from MBR to GPT.  You can use DISKPART for this.  Now your system drive is wiped and formatted GPT.  Boot into Macrium again.  Restore your back up image.  The program restores the MBR backup as GPT.  Run the FixBoot Utility when complete and when you restart, you'll have your OS just as it was, but formatted GPT. 

If you don't care about your install and have your data backed up...  Just grab your install media, make changes to your BIOS, and install as UEFI.  When you get to the point where you select your target disk for install, press shift+F10 which will open a command prompt... run DISKPART and format GPT.  Now install your OS. 

It looks more complicated than it is.  Macrium has proven very reliable.  Hope this helps. 
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Re: Converting from BIOS to UEFI
« Reply #2 on: November 22, 2017, 11:07:13 pm »
Sorry I haven't responded for so long but I forgot I had posted on this forum. I've also been busy on another forum and forgot completely about this one - sincere apologies.

As far as my message is concerned I have now done the conversion. Yes, I knew I couldn't do anything just by changing settings in the F/W but it was the settings I was worried about. As it happens I was advised not to change any settings at all since 'UEFI and Legacy' was already selected. What does bother me though is that I don't have a "Secure Boot" setting I can disable so I can boot up using a bootable CD/DVD as I understand you have to disable "Secure Boot" to do that.

So what can I do? How do I boot with a bootable CD/DVD? I've got several sorted out in case of emergency and if I can't boot up using them I shall be in a right state. Does the lack of a "Secure Boot" setting mean it's permanently enabled whilst in UEFI? I just don't know at present as I'm still learning what UEFI is all about.

Any help would be much appreciated. Thanks.
« Last Edit: November 22, 2017, 11:08:50 pm by TraceyW »