Clarify if I understand boot files

I have a mess of usb boot drives, many that have lost their paper labels and many where I forgot to label them when I created them. Uefi drives, mbr drives, supposedly combined uefi and mbr drives. Some formatted ntfs, some as fat 32. These drives were made using different methods; media creation tool, rufus, yumi, directly from the apps themselves. I need someone to clarify that what I think I know is correct, because the longer I deal with this the more confused I get. Here are my questions.

For Windows Installation USB Drives
1. If I use powershell get-disk and find a drive is partitioned gpt, it’s automatically formatted fat32 and only PURE uefi bootable…correct?
2. If a drive is formatted ntfs and partitioned as mbr, then it is only mbr bootable…correct?
3. If a drive is formatted as fat32 and partitioned as mbr, to find if it is both uefi and mbr bootable, I have to look for the boot files within. For uefi boot, there will be \efi\boot\bootx.64.efi file and for mbr boot there will be a \boot\etfsboot.com file…correct??

For Bootable tools USB Drives (ie: Macrium rescue or a Yumi multi-tool disk)
1. If they are formatted fat32 and partitioned mbr, there will be Boot and EFI folders with same file names as above in them if they were built on windows platform or in the case of a Linux boot disk or Yumi multiboot which is built on Linux platform, the grub files in both folders. Therefore they will boot both mbr and uefi...correct?

My goal is to combine some of these using yumi and to do away with a lot of them.

lgentry said:

I have a mess of usb boot drives, many that have lost their paper labels and many where I forgot to label them when I created them. Uefi drives, mbr drives, supposedly combined uefi and mbr drives. Some formatted ntfs, some as fat 32. These drives were made using different methods; media creation tool, rufus, yumi, directly from the apps themselves. I need someone to clarify that what I think I know is correct, because the longer I deal with this the more confused I get. Here are my questions.

For Windows Installation USB Drives
1. If I use powershell get-disk and find a drive is partitioned gpt, it’s automatically formatted fat32 and only PURE uefi bootable…correct?
You're mixing definitions
- You have two types of drive architecture: MBR or GPT.
- GPT drives can only boot as UEFI
- The partitions on a MBR or GPT drive can be formatted as you like ( etx4, Fat32, NTFS etc)

2. If a drive is formatted ntfs and partitioned as mbr, then it is only mbr bootable…correct?
- Depends on the MB. Most MB require a FAT32 partition to boot as UEFI so if it only has one NTFS partition it will probably only boot as Legacy.
- A MBR drive with a FAT32 partition can boot a Legacy or UEFI

3. If a drive is formatted as fat32 and partitioned as mbr, to find if it is both uefi and mbr bootable, I have to look for the boot files within. For uefi boot, there will be \efi\boot\bootx.64.efi file and for mbr boot there will be a \boot\etfsboot.com (depends file…correct??
Correct

For Bootable tools USB Drives (ie: Macrium rescue or a Yumi multi-tool disk)

1. If drives () are mbr and formatted as fat32, there will be Boot and EFI folders with same file names as above in them if they were built on windows platform or in the case of a Linux boot disk or Yumi multiboot which is built on Linux platform, the grub files in both folders. Therefore they will boot both () Legacy and uefi...correct?
Correct

My goal is to combine some of these using yumi and to do away with a lot of them.

Read above

Thank you so much. Sorry for the mixup in my terminology. I'm old and old school, so it was the hardest thing for me to understand at all when uefi systems came out.

I've always thought of gpt and mbr as being the way a drive is partitioned rather than architecture. In my mind architecture
has always meant whether it was x32 or x64 bit version of windows. I never thought in terms of legacy either. The only way I could keep it straight was think bios vs uefi bios. Bios=mbr with x32 or x64 (boot media formatted as ntfs) and Uefi bios=gpt with x32 or x64 (with boot media formatted fat32). When the media creation tool became available I realized a mbr system could boot from a fat32 usb. I never progressed further than that and guess I've been thinking incorrectly all these years about what architecture is.

Thanks for straightening me out. Now, let’s hope I’m not too old to remember it.