grub read error

[Cristobal Camilo Juan]

hi,
i've just installed grub (0.93) and i can't boot up anymore :]
i had grub before on that computer and it worked fine, now i installed
newer linux (Slack9), and grub and it doesn't want to work anymore

the disk is 4GB, partitions like this:
hda1 - / 
hda2 - swap 
hda3 - /usr 
hda5 - /var 
hda6 - /home 
all (except swap ;) ) are ext3 

i tried to install grub in two ways:
 
1)from booted system: 
# grub-install /dev/hda 
2)with grub booted from floppy: 
# root (hd0,0) 
# setup (hd0)

but the results are the same: GRUB read error

it stops before showing menu, shows that message and does nothing more,
only thing i can do is reboot

i have no idea why it doesn't want to work, especially that grub worked
on this computer before - i had RedHat 7.1 installed

-- 
When the power of love overcomes the love of power the world will know
peace. 
--Jimi Hendrix