pentiumspeed wrote on 2023-05-04, 15:51:
GPT is excellent format for partitions but you have to keep this in mind with OSes limitations.
Indeed. And as you say, also BIOS limitations. Only UEFI can boot from GPT.
What this boils down to is that you can use GPT on BIOS systems, as long as you use an extra disk that is standard MBR, so the BIOS can boot from that, and you can set up your boot manager there.
After all, booting is a two-stage process:
First the BIOS/UEFI loads the basic boot manager.
The boot manager will then load the actual OS.
This means that you can install a GPT-compatible boot manager on an MBR disk, so you can also boot into OS installations stored on GPT partitions.
I have a legacy BIOS system that is set up as follows:
First disk is a 1 TB SSD, formatted as MBR.
Second disk is a 4 TB SSD RAID0, formatted as GPT.
The system has Windows XP, XP x64, Vista x64, Windows 7, Windows 10 and Windows 11 installed.
The first disk contains the Windows bootmgr from Windows 11, which allows you to boot into any of these OSes, on either MBR or GPT partitions.
Windows 10 and 11 are installed on partitions of the GPT disk, and will be booted directly from there.
All the other OSes are installed on the first disk, as they cannot be booted from a GPT partition (at least, not with a legacy BIOS in the case of Windows 7).
With the exception of XP 32-bit, all the OSes can see and use the GPT partitions, so you can still use these disks to install applications on and store data.
I suppose with the hack mentioned in this thread, by replacing a device driver with one from a newer Server version, the 32-bit XP would also be able to see and use the GPT disks.