On Wednesday, 18 October 2023 18:45:27 BST Neil Bothwick wrote:
> On Wed, 18 Oct 2023 10:23:23 +0100, Michael wrote:
> > > Oh, and if you use GPT, you no longer need the MBR compatibility
> > > partition, or whatever its called. I no longer need it so I can't
> > > remember the exact name.
> > 
> > Man pages of partitioning tools refer to it as "Protective MBR",
> > although I've seen it mentioned in the interwebs as "protective GPT",
> > which I think is more accurate.  It uses the first sector (LBA 0) to
> > store an MBR table showing the whole disk, or 2TB if smaller, as an MBR
> > partition.  This is the first partition on the disk, typically 1 MiB in
> > size.  It is meant to stop 20 year old partitioning tools from messing
> > up a GPT partitioning scheme because they can't see it.  Arguably
> > nobody uses Windows 98 these days, so it should be safe to not have a
> > protective MBR on your GPT disks.
> 
> You need it if your hardware doesn't support EFI booting.

Yes, quite right, a 4TB disk on a BIOS MoBo would need a GPT partitioning 
scheme to access all 4TB, but with an old MoBo you'd use a BIOS Boot Partition 
and GRUB as mentioned by Grant.