SSD is in GPT, HDD is in MBR format. Is that OK?

NRT · 08 Oct 2018

Hello,

Recently I've purchased a Kingston 240GB SSD. I initialized the SSD in GPT, and installed Windows 10. But, when I looked my 2TB HDD partitions, they are in MBR format. Will there have any stability issues when the SSD is in GPT and HDD in MBR? Do I need to change my HDD to GPT for system stability?

Thank You,

EdTittel · 08 Oct 2018

No problem using MBR drives on your system, along with a GPT boot drive. The only time it matters really is when booting, and then because GPT is required to boot in UEFI mode (MBR boot aka CSM boot [Compatibility Support Module] only works with legacy BIOS). See this MS Windows and GPT FAQ for more discussion.
HTH,
--Ed--

NRT · 08 Oct 2018

EdTittel said:

No problem using MBR drives on your system, along with a GPT boot drive. The only time it matters really is when booting, and then because GPT is required to boot in UEFI mode (MBR boot aka CSM boot [Compatibility Support Module] only works with legacy BIOS). See this MS Windows and GPT FAQ for more discussion.
HTH,
--Ed--

Many thanks.. would you kindly tell the differences, if I opt for the GPT format same for HDD and SDD ?

NavyLCDR · 08 Oct 2018

EdTittel said:

No problem using MBR drives on your system, along with a GPT boot drive. The only time it matters really is when booting, and then because GPT is required to boot in UEFI mode (MBR boot aka CSM boot [Compatibility Support Module] only works with legacy BIOS). See this MS Windows and GPT FAQ for more discussion.
HTH,
--Ed--

GPT is NOT required to boot in UEFI. Most computers require a FAT32 partition to boot from in UEFI, but no computer requires GPT to boot in UEFI.

Kyhi · 08 Oct 2018

GPT format allows for up to 128 primary partitions
MBR just 4 primary partitions...

Faith · 08 Oct 2018

NavyLCDR said:

GPT is NOT required to boot in UEFI. Most computers require a FAT32 partition to boot from in UEFI, but no computer requires GPT to boot in UEFI.

Not to drive off-topic here. But please enlighten me how you manage to do this? Because I have never gotten MBR to work in a UEFI boot, it just gives a C: check powershell fail. I've always had to format the C: drive to GPT in order to get a required EFI partition.

NavyLCDR · 08 Oct 2018

Faith said:

Not to drive off-topic here. But please enlighten me how you manage to do this? Because I have never gotten MBR to work in a UEFI boot, it just gives a C: check powershell fail. I've always had to format the C: drive to GPT in order to get a required EFI partition.

The way I have done it in the past is to create a 100mb FAT32 partition. Then create the NTFS partition for Windows. Use the DISM /apply-image command to write Windows to the NTFS partition. Use the BCDBOOT command to make the FAT32 partition UEFI bootable. You need to do a couple more steps to make the FAT32 partition bootable in both UEFI and legacy BIOS modes (mark it af active and run a bootsect command on it).

Also, if you have an MBR drive booting in legacy BIOS mode, all you need to do to boot in UEFI is replace the NTFS system reserved partition with a FAT32 partition. There is no need to convert the drive to GPT just to boot in UEFI mode.

Kyhi · 08 Oct 2018

Ask yourself - how does a single partition USB - boot both UEFI and legacy ??

cereberus · 08 Oct 2018

Kyhi said:

Ask yourself - how does a single partition USB - boot both UEFI and legacy ??

Yep - from good old Wikipedia further below.

It clearly states UEFI can use both mbr and gpt.

Of course, gpt drives have many advantages (I like others tend to rather erroneously say difference between uefi and bios is ability to have more than four partitions which is not actually strictly true as it is the difference between an mbr and gpt drive that determines that).

Disk device compatibility

In addition to the standard PC disk partition scheme that uses a master boot record (MBR), UEFI also works with a new partitioning scheme called GUID Partition Table (GPT), which is free from many of the limitations of MBR. In particular, the MBR limits on the number and size of disk partitions (up to four primary partitions per disk, and up to 2 TiB (2 × 2⁴⁰ bytes) per disk) are relaxed. More specifically, GPT allows for a maximum disk and partition size of 8 ZiB(8 × 2⁷⁰ bytes).