UEFI machine works fine, but boots as if it was a Legacy system.

[parama3500]

I recently upgraded to a new PC, an i3 4th Gen and was surprised to see the new technology given that I upgraded from an ancient Core 2 Duo.

The shopkeeper installed Windows 10 for me and it works as an intended UEFI system: Windows logo doesn't appear but loading circle appears under the motherboard logo. It also had a boot entry 'Windows Boot Manager' in BIOS.

I upgraded to a new HDD and I by myself installed Windows 10 on to it. I learnt that UEFI requires GPT partition style, I can't remember if I formatted my HDD to GPT, I assume so because the Windows 10 setup went fine without errors.

Windows 10 works fine here! No worries! But, no more 'Windows Boot Manager' boot entry and the motherboard logo disappears and the Windows logo and loading circles appear as if it was an old legacy machine.

And disk management shows that my disk has MBR partition style, so I guess I found the culprit.
How can I fix this?

Thanks.

 

[stdragon]

If the BIOS was set to legacy, then when you install Windows 10, you'll only get the default option to install in MBR mode on the primary boot device (C drive). The problem with MBR is that you can only have the first partition be up to 2TB in size.


https://docs.microsoft.com/en-us/windows-server/storage/disk-management/change-an-mbr-disk-into-a-gpt-disk

NOTE: the above link will erase data. It's better to just run the CLEAN command and reinstall Windows. Be sure to backup your data first

 

[CountMike]

Just check Disk Management, there should be an UEFI partition that doesn't appear in legacy mode. As far as MB logo not appearing during BOOT, it can be enabled or disabled in BIOS and/or fast boot may be enabled.
That Docs is outdated, with newer W10 it canbe converted to GPT/UEFI without data loss, I did it myself when switching from MB with Legacy BIOS to one with UEFI: https://www.windowscentral.com/how-convert-mbr-disk-gpt-move-bios-uefi-windows-10