jdolecek@per4mance.cz said:
> parameters to be used for BIOS calculations are: cylinders=8374
> heads=16 sectors/track=63 (1008 sectors/cylinder) 

That's probably wrong for your multi-OS setup
(must be <1024 cyls).

> Information from DOS bootblock is:
> 0: sysid 7 (OS/2 HPFS or NTFS or QNX2 or Advanced UNIX)
>     start 63, size 4199265 (2050 MB), flag 0x80
> 	beg: cylinder    0, head   1, sector  1
> 	end: cylinder  261, head 100, sector 63
-----------------------^^^
> 1: sysid 165 (FreeBSD or 386BSD or old NetBSD)
>     start 4201344, size 2252880 (1100 MB), flag 0x0
> 	beg: cylinder   72, head   0, sector  1
------------------------^^
> 	end: cylinder  258, head  15, sector 63

Not very likely...
I'd figure out what the BIOS thinks about the disk geometry
now (you didn't fiddle with the settings?!?) and set up
the MBR partition table again.

best regards
Matthias