Booting gpt partition with non-UEFI MoBo

[fonon]

Is it possible to boot Windows 10 from gpt partition using non-uefi mobo? I have a 4TB disk and windows installer refuses access to gpt partition. Any idea how to solve this problem? Can I install system on mbr partition and next convert it to gpt? Will it be bootable?

 

[Colif]

Legacy bios can't boot GPT drives as they don't understand the disk layout. MBR drives have their boot partition as 1st partition on drive
For example -

whereas GPT drives can have the boot partition anyway on drive so on this PC its 2nd partition -

Both examples are same PC, only difference is format of ssd
Legacy boot method only looks in 1st partition and if it doesn't find the files its looking for, will try next drive or just throw an error at you

Only way to boot off drive is to make it MBR, and MBR can only access 2.2tb of space, so 1.8tb of the drive would be invisible to the motherboard.

How old is the motherboard as most since 2009 should have some support for GPT. I would buy a smaller drive,m make it MBR and use the GPT drive as stoirage as most motherboards in last 9 years should allow you to format storage drives as GPT.

 

[SkyNetRising]

Is it possible to boot Windows 10 from gpt partition using non-uefi mobo? I have a 4TB disk and windows installer refuses access to gpt partition. Any idea how to solve this problem?

Put bootloader on a different non-GPT drive and install windows on GPT drive.

Can I install system on mbr partition and next convert it to gpt? Will it be bootable?

If your system can't boot from GPT, you install in MBR, convert to GPT, obviously your system won't be able to boot anymore.

 

[fonon]

Thank you for answers. I'm not an expert, but I think the mobo can boot gpt partition (how to chech it?). The problem is Windows limitation to use gpt only with uefi, so I can't install system on gpt partition because the mobo is non-uefi.
Can I convert mbr to gpt and use bootmanager on another disk?

 

[SkyNetRising]

It would be easier just to install windows in legacy mode on a smaller drive and use 4TB drive as secondary storage drive.

BTW - what's the model name of your motherboard?

 

[fonon]

Gigabyte P55A-UD7 mobo. Unfortunately, Windows must be installed on 4TB disk. The additional disk may be used for bootmanager.

 

[USAFRet]

Gigabyte P55A-UD7 mobo. Unfortunately, Windows must be installed on 4TB disk. The additional disk may be used for bootmanager.

Specifically, why must the OS be installed on that 4TB drive?

 

[SkyNetRising]

Ok, then. This is, how you do it.

• 1. Install 2 drives in your pc - small one for bootloader and big one - 4TB for windows;
  2. partition small drive into MBR, create small 500MB bootloader partition on it (primary, active, ntfs);
  3. partition 4TB drive into GPT, create windows partition on it (size at least 100GB, primary, ntfs);
  4. Install windows in legacy mode, specify windows location on 4TB drive;

That's it.

 

[fonon]

What means 'legacy mode'? I tried to install Windows on GPT disk. The second MBR disk was present in the system. There was no option to install the bootloader on one drive and the system to another.

 

[SkyNetRising]

If your system can boot into legacy mode only, then this is only mode you can install.
If your 4TB drive is partitioned in GPT and there is partition on it, then bootloader automatically will get placed on MBR drive.

 

[USAFRet]

MERGED QUESTION
Question from fonon : "MBR partition and large disks"

Hello,
I have an old MB (no UEFI) and large 4TB disk. The Windows 10 installer can't write the operating system on the gpt parted disk, so I will try to use the mbr partition. I can't find a complete description of mbr partition standard. Some authors write about 2TB limit related to disks, another to single partition. Could I use 4 primary partitions, each below 2TB? Is it possible to create 3 primary and one extended partition (below 2TB limit) with many logical drives?
f.

 

[USAFRet]

MERGED QUESTION
Question from fonon : "Bootable pci-e controller and non-uefi mobo"

Is it possible to boot windows 10 on gpt partition using pci-e controller on motherboard with classic bios only?

For windows 10/x64

BIOS boots only on an MBR disk .

However, GPT is supported for storage drives.

 

[USAFRet]

Please...keep this all in one thread.
Respondents lose all the backstory and information.

 

[karenjoly]

Here is a round about way I haven't tried. With only minimal coffee this am, it sounds feasible but the op needs a second drive .

Install windows on an MBR drive, then clone that install to the GPT drive.

According to Macrium, this can happen.

"The GPT disk will have a small (128 MB) partition at the front of the disk. If you copy your source partition(s) to the free space after this partition then the target disk will retain its GPT state. "

http://reflect.macrium.com/help/v5/how_to/conversions/convert_an_mbr_disk_to_a_gpt_disk.htm

Sweet!

 

[fonon]

Please...keep this all in one thread.
Respondents lose all the backstory and information.

It's not a good idea. Threads are related to certain aspects, but more are different. They will address more general issues.

Here is a round about way I haven't tried. With only minimal coffee this am, it sounds feasible but the op needs a second drive .
Install windows on an MBR drive, then clone that install to the GPT drive.
According to Macrium, this can happen.
"The GPT disk will have a small (128 MB) partition at the front of the disk. If you copy your source partition(s) to the free space after this partition then the target disk will retain its GPT state. "
http://reflect.macrium.com/help/v5/how_to/conversions/convert_an_mbr_disk_to_a_gpt_disk.htm
Sweet!

It's a kind of hybrid partition with mbr at front of the disk?

 

[SkyNetRising]

I gave you way to do it - 4 steps part.
You still haven't tried it?

 

[fonon]

1. Install 2 drives in your pc - small one for bootloader and big one - 4TB for windows;
2. partition small drive into MBR, create small 500MB bootloader partition on it (primary, active, ntfs);
3. partition 4TB drive into GPT, create windows partition on it (size at least 100GB, primary, ntfs);
4. Install windows in legacy mode, specify windows location on 4TB drive;
(...)
I gave you way to do it - 4 steps part.
You still haven't tried it?

You didn't answer what means "Install windows in legacy mode"?

I tried to install windows on 2 disk system (mbr + gpt disks) before. There was no way to specify two partitions - one for bootloader and second for system.
f.

 

[SkyNetRising]

I think, I answered it.

If your system can boot into legacy mode only, then this is only mode you can install.
If your 4TB drive is partitioned in GPT and there is partition on it, then bootloader automatically will get placed on MBR drive.

There are 2 possible boot modes - UEFI and legacy. Since your system can't boot in UEFI, only legacy is available. You don't have to worry about it.
You have to specify only, where windows will be installed. Bootloader automatically will go onto MBR partitioned drive.

 

[fonon]

I think, I answered it.
(...)There are 2 possible boot modes - UEFI and legacy. Since your system can't boot in UEFI, only legacy is available. You don't have to worry about it.
You have to specify only, where windows will be installed. Bootloader automatically will go onto MBR partitioned drive.

You wrote about windows installation in legacy mode, but it's boot mode. Now it's clear.
As I wrote this method doesn't work due to windows 10 limitation. There is no way to select GPT partition.
f.

 

[SkyNetRising]

As I wrote this method doesn't work due to windows 10 limitation. There is no way to select GPT partition.f.

Why not? Do you get any error?

 

[fonon]

Why not? Do you get any error?

Because Bill Gates has set a limitation. The installer disables the disks with GPT partitions.
f.