On Mon, Apr 03, 2000 at 04:02:06PM +0200, Wolfgang Solfrank wrote:
> The bios on newer PCs can access a disk with two methods.  For compatibility,
> it supports the old method with its 1024 cylinder limitation.  The newer
> method allows access to much larger disks (I'd have to look it up again,
> if you need to know the exact number, but believe me, there is quite some
> room left, even with todays rapidly growing disk sizes).

Right. int13 extensions use a 64bit LBA. The tighter limit when it comes
to booting is the 32bit LBA in the MBR, which puts the limit at
2^32 sectors. Sector size is currently always 512 bytes, which puts
the limit in bytes at 2TB.

The int13 extensions interface allows for sectors up to 65536 bytes,
as retrieved through the "get drive parameters" call. So if BIOSs
will ever return a sector size > 512 (I very much doubt it), that
would put the limit at 256TB.

- Frank