What would it take to be able to boot from >4BG devices

[Thomas]

If i understand how things work it's a matter of putting an appropriate file system, ie. PFS3, on the ROM chip.

No, that's not true. The file system can be stored in the RDB area of the harddisk, so it can easily be upgraded without hardware change.

The major issue is the device driver (for example scsi.device). It is in ROM and needs to be replaced.

Even worse, the only driver which is in Kickstart is the driver for the IDE or SCSI controllers on the mainboard. Every other controller has its own driver in its own ROM. So changing the Kickstart ROM has no effect on third-party controllers.

OTOH if you have a HDD controller which already supports large harddrives, you don't need to change anything. For example if you have an accelerator from Phase5 with SCSI controller, you can install PFS3 on HDD and create boot partitions of any size and location.

There is no easy answer to your thread title. There is a different solution for each HDD controller and for some controllers there is no solution at all.

[Thomas]

Can you explain what storing it in the RDB means?

In HDToolbox, click on Partition Drive, then on Add/Update (in 3.1 HDToolbox you have to activate the "advanced options" checkbox for the Add/Update button to appear).

Then you see a list of file systems in the RDB of this disk. Here you can remove, add new or update existing ones. When you add one you have to enter an identifier (a.k.a. DosType). Do not leave the default, use the one mentioned in the installation instructions of the respective file system.

For more details read the manual of PFS3.

I had, I guess, always assumed that when partitioning the drive, it was doing as such.

HDToolbox automatically adds FastFileSystem to the disk. If you want to install a third-party file system like PFS3 or SFS, you always have to go through the manual process.

Just to clarify, you can boot from any sized device, its just the boot partition that needs to be in the 1st 4 Gig.

Yes, that's right. To be more precise: the boot partition must be accessible by the ROM driver. Once it starts to boot you can load additional/updated drivers from disk.