Which best MBR or GPT - fomatting NVMe M.2s; Why?

I read Shawn's tutorials on Formatting ( MBR vs GPT), but I have a related question. How does Disk Mgr determine the default? And which is better? Attachment 285816See attachment.

ONG,
Thanks for quick reply. I'll read article, thanks. I'm new to Win10, but slowly starting to like it --- but LOTS to learn; deviations from Win 7 which I'm much more familiar with.

My question was on Disk Mgr choice of defaults for new M.2 drives. But article will help, thanks.

I don't believe that Windows Disk Management has a default. When you first initialize a blank or new disk it asks you which format you want to use - MBR or GPT. It's your choice.

There are many goods reasons to use GPT in a modern system with a modern operating system. The only reasons I can think of to use MBR in a modern system is for specialized reasons, perhaps dual booting with another OS that needs MBR.

Other than being able to support partitions larger than 2TB, GPT also takes a fraction of a second less to initialize during boot up if that matters.

What I do is I initialize my main drive which is an NVMe m.2 SSD as GPT and my 2nd drive which is a 2.5" SATA SSD as MBR simply because that way I ensure that Windows does not place any boot files on the 2nd drive when I re-format because it won't if the 2nd drive is not initialized in the same format which makes me not have to physically remove or disable the 2nd drive as I am reinstalling Windows.

Anibor & TV2,
Much like many of you here, I’ve formatted so many disks over the years, I have grown to trust the defaults, except for naming the new drive. I should pay more attention to the choices, but sometimes in a hurry and little attention.

On this particular issue, I don’t recall selecting MBR on the 250GB drive, especially since I forgot the diff betw MBR & GPT. Even if there is no system default as claimed, perhaps MBR is highlighted at top and I just clicked OK. Becoming more lax in old age, I mistakenly assumed the system would choose the best default. But now I know better thanks to replies here. And you’re right, GPT seems best after my research. Thanks to all.

Spartan,
You make a good point; especially since I too use 2.5 SSDs for user files along with the M.2s.

NavyLCDR said:

On a blank drive from the factory, if you create a partition on it using native Windows tools you will get MBR (and the 2TB limit associated with it). So I guess that could be considered the default. Once a DATA drive is MBR or GPT, it will stay that way, by default, when creating new partitions on it, unless you issue a command to convert it to MBR or GPT.

During Windows setup, if the drive is all unallocated space, then Windows setup will convert the drive you are installing to depending on which mode you booted from - legacy BIOS (CSM) mode gets MBR, UEFI mode gets GPT.

I'm new to W10 when I purchased this Sager laptop only for the internet commo after my not-so-trusty ASUS laptop fried the memory for some reason. Now I learn more and more with each W10 issue. This thread started with my question why my 250GB M.2 got assigned MBR. And wanting all GPT with W10, I thought I must use Shawn's solution to convert 250GB drive to GPT. Then after doing a clone from the "C" drive (GPT fr factory) -- I discovered the cloned 250GB M.2 got converted to GPT during the cloning proc. I remain amazed at how much I don't know after 30 years experience with computers (building and operating). So problem solved automatically.