Strange things with my hard drive

Victor Tsaran tsar at
Tue Feb 26 11:05:42 EST 2002

Hi, Kerry!
I think I am going to collect your very informative messages. Are there any
copyrights on them?!
When I ran Western Digital Lifeguard floppy, it told me that int13H is not
supported and that BIOS is not controling your device.
Also, a strange thing happens here.
When I switched 40-pin cable for 80-pin cable, Windows XP would not start,
and only after I, in despair, reflashed BIOS, everything started to work
normally. Don't know what to think about all of this.

----- Original Message -----
From: "Kerry Hoath" <kerry at>
To: <speakup at>
Sent: Tuesday, February 26, 2002 1:08 PM
Subject: Re: Strange things with my hard drive

> Some boards don
> 't like talking to drives over 28gb or so. but I doubt this is
> your problem.
> The reality is that you can only get at  8.4gb of disk in chs mode
> i.e. standard int13. It works like this:
> int 13 function call 2 read sector.
> registers:
> ah=2 al=number of sectors.
> es:bx points at area of memory to receive data.
> dh=head 1-255
> dl=drive letter: 0 for a: 1 for b: 80 for hard disk 1 81 for hard disk 2.
> cl=cylinder 0-255
> ch=sector to start reading from 0-63 top 2 bits of ch are top 2 bits of
> This gives us a sector range of 1-63 and
> a cylinder range of 0-1023.
> 1024 cylinders 255 heads and 63 sectors per track gives you a maximum
> capacity of 8.4gb or so.
> To read beyond that you need to use LBA (Linear block addressing)
> and to use that in bios you must use the phoenix int13 extentions.
> Dos can't use int 13 extentions or at least
> versions up to 6.22 can't.
> Dos also can't boot beyond 2gb on a disk due to a calculation bug in the
default dos boot sector.
> Newer lilo versions i.e. 20 and up can use int13 extentions.
> Older versions can not. If your bios has int13 extentions most things
after 1994 do you can place your linux partitions wherever assuming ide.
> Scsi it all depends on the onboard scsi bios.
> Lilo 20 and up can boot just about anything on a new machine. lilo <20 or
> a bad bios and you'll need to keep linux /boot partition below the first
8.4gb so
> the bios can load the kernel or stick a floppy in the drive.
> Yes I have no life but perhapse this may clear up some of the
> incomplete/missinformation on this topic floating around.
> Once the kernel is booted linux's ide driver uses lba when available and
can access
> up to 4 terabytes since kernel 1.1.51 or so.
> Getting the kernel loaded still requires co-operation from the bios and
your boot loader of choice
> lilo grub silo nt boot loader system commander etc.
> Regards, Kerry.
> On Tue, Feb 26, 2002 at 12:14:56AM +0100, Victor Tsaran wrote:
> > Well, I don't know what the biggest size the motherboard supports, but
> > been running my 20GB hard disk with no probs before on this same
> > motherboard.
> > Vic
> >
> >
> >
> >
> >
> >
> > _______________________________________________
> > Speakup mailing list
> > Speakup at
> >
> >
> --
> Kerry Hoath:  kerry at kerry at or
kerry at
> _______________________________________________
> Speakup mailing list
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