Windows wont boot 3tb with uefi?

[Lee400]

Can anyone give me any information as to why my z77 board cannot boot a 3tb hard disk formatted to gpt specifications?

[Dark Mantis]

Hi and welcome.

From memory although Windows can see and use a 2.2TB drive as long as it is formatted in GPT it can't boot off it.

[ysw521]

when you install os in to 3TB hdd. your boot priority should be UEFI-ODD device, not ODD device.   and your HDD should be UEFI-HDD, not HDD.
you can check this.

[Lee400]

With a standard bios you are correct, but with uefi and a gpt configured hard disk windows should see and also be able to boot hard drives well in excess of 100 terabytes or more?

[Dark Mantis]

Yes, my bad. I forgot that you were using UEFI. 

With that in mind I can't think of any reason why it shouldn't boot.  Exactly how have you got the settings at the moment ?

[Lee400]

Well I got the drive in ahci, drive detected in bios (correct size reported), boot into windows pe from instalation media efi option and the drive reads 1.8 tb, will only detect 2.8tb if you install the intel ahci drivers from motherboard media , which are only really provided for win xp compat and shouldn't need to be added to a windows 7 x64 version. It will carry on installing until almost complete. Then an error message something to the effect windows was unable to be installed, reboot and restart instalation. I have even set up the partitions on the disk manually using 'diskpart' cmd. Efi system partition, msr reserved partition and windows primary partition created GPT layout, same error!