Re: grub stopped working after motherboard swap

[Jochen Hoenicke]

On May 9, Ken Huisman wrote:
> Hi,
> 
> I was using grub on my pc to dual boot windows and linux and
> I recently swapped out my motherboard and on the new one it
> gives me an error.  Here are the details:
> 
> Old motherboard was an abit BH6, /dev/hda and /dev/hdb were
> windows disks, /dev/hdc linux and /dev/hdd cdrom.
> 
> Grub booted linux and windows fine off this configuration
> 
> I swapped out my motherboard for an Asus A7V133
> and now when I boot up I get the following:
> 
> GRUB loading stage 1.5
> GRUB loading, please wait...
> Error 18

This is ERR_GEOM: Selected cylinder exceeds maximum supported by BIOS.
Maybe the BIOS on your new motherboard doesn't support LBA mode or you
need to reinstall grub the --force-lba flag.

Another possible cause is that the new bios maps the hard disks in a
different order and grub tries to access another (smaller) hard disk.
Try booting from a grub floppy and issue the geometry command for
(hd0), (hd1) and (hd2).  You should see from the partition table which
hard disk is which.

> Other info: If I boot linux off a floppy it works fine, however
> windows ME seems to have trouble seeing the secondary IDE
> channel (I am almost to the point of taking the whole thing back).

Grub completely relies on the BIOS to access the disks.  If your BIOS
doesn't map the secondary IDE channel you are out of luck.  Try
putting the linux boot partition on a different disk.

  Jochen