OS Drive Not Recognized As UEFI

S

Synthesize

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Oct 16, 2013
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It is to my knowledge that the drive needs to be recognized as UEFI before you install Windows 8 on it, unfortunately I forgot about the feature before installing the OS. My main drive is not listed as UEFI in BIOS currently, how will I able to get it to recognize as one again?

Do I need to reformat in order to get the UEFI features or are there other alternatives to this? I don't want to have to reformat everything again.

Any suggestions?

Current setup:
i7 4770k
GTX 780
Gigabyte Z87X-OC-Force
OCZ-Vertex 4 SSD 128gb
 
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It needs to be formatted with the GPT partition table instead of MBR.

In this walkthrough, go to the "Configure drive using an UEFI motherboard and GPT format" section and click the "Click here to see guide!" for step by step instructions on using DiskPart to format with GPT with the Windows 8 install disc.
 
At this point, can I avoid reformatting? Is it even worth reformatting for the benefits of UEFI alone?

I'm trying to avoid spending another few hours re-installing everything but if you can persuade me to do it for the benefits alone, I might as well.

Is it possible to clone the drive, reformat with GPT partition, then clone it back?
 
After reading through that amazing guide, I'm going to just go ahead and reformat. I rather just do it and get it over with and do a clean install of 8.1.

I think I also figured out why it didn't format it as UEFI to begin with...

"...unless you disable the Compatibility Support Module (CSM) either directly with a setting in the BIOS, or via enabling Secure Boot (disabling CSM is a side affect of this), a Windows installation otherwise configured for EFI booting will not boot in EFI mode."

I'm going to give this a try, thanks.
 
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I was under the impression that if you completely cleaned the drive you intend to install win 8 to, so that it shows as a new unused drive and the BIOS was set to UEFI then the windows 8 install would automatically format the OS drive as a GPT drive.

That's what I did with my win 8 install but then I was using a SSD and had done a secure erase on it and that totally nuked the entire drive. The win 8 install created GPT partitions.
 
If you have UEFI enabled or boot to UEFI Windows PE, you can press Shift+F10 for CMD and simply run the Clean command in diskpart to remove MBR and allow the setup to install as GPT.
 
It seems that I'm having another issue here. While I was able to partition the SSD to GPT and configure it to UEFI during the windows installation, the BIOS now only shows Windows Boot Manager as the only drive under boot sequence, without it being listed as UEFI. None of my other drives are listed at all. The optical drive doesn't show up in the bios boot sequence either, which I made sure it was UEFI before installing the OS.

Windows 8.1 does boot up fine and it seems that UEFI is working so I'm not understanding what the problem seems to be here. I followed the directions in the guide posted above and all my drives are working fine in the OS. I did run into the "SecureBoot isn't configured properly" watermark in 8.1 but all I had to do was reset my secure boot keys in the BIOS and it went away.

Any ideas? This is getting really frustrating as I didn't have any of these problems with UEFI on my other Z87 system.
 
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Here are some screenshots to give you a better sense with what I'm dealing with. The only way to have my other drives show up is to disable Windows 8 features in the bios, which would disable UEFI altogether.

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The mistake that I see most for EFI installs is the issue of using USB drives that are not formatted FAT32 for EFI installations; many format the USB drives as NTFS and that is the mistake. To be EFI you must boot from an EFI capable drive too, and that has to be FAT32. It seems that you have everything set. This may just this may be the problem.
 
I actually used the install disk instead of USB but I made sure the optical drive was UEFI before installing the OS on the SSD.
 
It seems like the "second time" you had it right. You mentioned: "the BIOS now only shows Windows Boot Manager as the only drive under boot sequence." This is what you should see with EFI booting. However, it seems that you may just need to clear the keys and start fresh; keys and install that is to get Secure Boot to be proper. Or you may be able to unload and load keys and it may be fine.

Curious are any of the other disk, if any you use, MBR?
 
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I believe SecureBoot is properly configured now after I reset the keys because the watermark doesn't show anymore. I'm currently using 2 MBR drives and 3 GPT drives (one of them being the ssd).

I did make sure all of my data drives were disconnected during the OS installation. Only had the optical drive and SSD connected throughout until I finished installing all of the drivers.

Are you suggesting I reformat and install the OS again after resetting the keys?

Thanks.

Edit: I'm going to reformat tonight, making sure the SecureBoot keys are reset, with CSM disabled and Windows 8 features on. I'll report back later... thanks for the help everyone.
 
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