[ltp] maximum supported harddisk size for T42 and T23

[Karel Podvolecky]

Hi,

Martin Steigerwald napsal(a):
> Am Donnerstag 22 November 2007 schrieb Karel Podvolecky:
>> Hi,
> 
> Hi!
> 
>>   generally I think it's not a BIOS who in fact limits maximum drive
>> size. It's interface itself.
>> EIDE interface has 137GB limit. Newer EIDE ( I think ATA-7 specs)
>> supports LBA48 addressing which supports much larger capacities than
>> todays disks can reach.
>>
>> To investigate, run 'hdparm -I /dev/hda' and look if there is line:
>> "48-bit Address feature set" with star mark (*). If not, you have limit
>> 137GB drive (so 120GB drive should be fine).
>>
>> And to BIOS stuff:
>> BIOS can limit capacity only to boot an OS. After linux kernel loads,
>> it loads it's own EIDE (PATA) driver, which isn't depend on BIOS, so
>> you can see all capacity supported by interface. In this case, there
>> may be problems with identification of partitions in newer computer,
>> because it has different CHS used to create them, but if you use it
>> only in your notebook, it should be fine. And little 1024 cylinder
>> warning: I suggest you to create first partition as /boot, so BIOS can
>> see it.
> 
> Thanks to everyone for their answers!
> 
> I am not that much into limits on the PC architecture as I come from the 
> Amiga originally. Well there has been limits as well but they were raised 
> considerably which each step. OFS was unusable for harddisks bigger 30MB 
> I think, then there as a 4GB (32 bit) limit, then I think there also has 
> been a 137 MB limit and I am not absolutely sure whether this has been 
> resolved, but I think so.

137GB limit is resolved by LBA48 addressing (2^48 is quite bigger: 262 TB).

> 
> Ciao,

cheers
kapo