grub> root (hd1,
 Possible partitions are:
   Partition num: 0,  Filesystem type unknown, partition type 0x7
   Partition num: 4,  Filesystem type unknown, partition type 0x7
   Partition num: 5,  Filesystem type unknown, partition type 0x82
   Partition num: 6,  Filesystem type is reiserfs, partition type 0x83

grub> root (hd3,
 Possible partitions are:
   Partition num: 0,
Error 18: Selected cylinder exceeds maximum supported by BIOS
   Partition num: 1,
Error 18: Selected cylinder exceeds maximum supported by BIOS
   Partition num: 2,
Error 18: Selected cylinder exceeds maximum supported by BIOS
   Partition num: 3,
Error 18: Selected cylinder exceeds maximum supported by BIOS

grub> root (hd0,4)
grub> root (hd2,4)