Fdisk disagreas with BIOS over 120GB drive.
Siegbert Baude
Siegbert.Baude at gmx.de
Tue Aug 19 09:14:19 PDT 2003
Hi,
>>Fdisk (using /stand/sysinstall) disagrees with the values my bios is
>>reporting. My BIOS reports that my 120GB drive has this geometry: 59131
>>Cylendars, 16 Heads, and 255 sectors. The drive is an IBM deskstar. When i
>>try to enter the correct geometry, Fdisk gives me the message below.
>>
>>---------start message---------
>> Message
>> WARNING: A geometry of 59131/16/255 for ad2 is incorrect. Using
>> a more likely geometry. If this geometry is incorrect or you
>> are unsure as to whether or not it's correct, please consult
>> the Hardware Guide in the Documentation submenu or use the
>> (G)eometry command to change it now.
>>
>> Remember: you need to enter whatever your BIOS thinks the
>> geometry is! For IDE, it's what you were told in the BIOS
>> setup. For SCSI, it's the translation mode your controller is
>> using. Do NOT use a ``physical geometry''.
>> (100%)
>> [ OK ]
>> Press enter or space
>>----------end message----------
>>
>>
Sorry, i just had a closer look at the CHS numbers 59131/16/255 fdisk
spits out and it is completely correct, this is no valid geometry!
For all the glory details read:
http://www.ata-atapi.com/hiwchs.htm#T5
In short, the number of sectors should be <=63. I remember, that I had
the same problem with an Samsung SV1204H (also 120GB) and an Abit-BX133.
I had to manually insert the correct numbers there. The disk reports
232632/16/63, but due to a small bug in the BIOS, I couldn't choose a
cylinder value of 232632. So I used the 14596/255/63 mode. Note, that
the sector number in both cases is <=63. The number of cylinders can
slightly vary for your IBM disk.
So I suggest to erase the partition table as I described before and then
force the BIOS to use either the 16/63 (if possible) or 255/63 mode.
Ciao
Siegbert
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