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No detected harddisk & less capasity than normal

Last response: in Storage
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July 28, 2009 3:47:32 AM

I HAVE A PROBLEM WITH MY HARDDISK (SEAGATE ATA 160GB),MY COMPUTER CAN'T DETECT THIS HARDDISK (EVEN MY BIOS OR IN MY COMPUTER). BUT IF I TRIED TO LOOK IN HARDWARE IN MY SYSTEM IT CAN BE DETECTED. BUT IF I TRIED TO FORMATED WITH ANOTHER COMPUTER, MY HARDDISK DETECTED ONLY 32GB WHY? ACCTUALLY MY HARDDISK CAPASITY IS 160 GB. HOW TO FIX MY PROBLEM? HELP ME PLEASE!!!
July 28, 2009 4:08:11 AM

well

first you ought to fix your capslock.....then we'll move on to the HDD
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a c 127 G Storage
July 28, 2009 12:57:05 PM

Your motherboard/BIOS/operating system doesn't have 48-bit LBA support, meaning it doesn't support drives larger than 128GiB. You need Windows XP SP1 or later to get 48-bit LBA support. You can also create a 128GiB partition and partition the remaining portion of the disk after you've (re-)installed Windows.

So just insert a CD/DVD with windows setup and format/partition the disks from there.
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a c 349 G Storage
July 28, 2009 2:47:09 PM

This does NOT sound anything like a problem with 48-bit LBA Support.

The 32 GB number may be a clue. Check it again - it may be 32 MB. That is a common size of the BUFFER RAM located on the hard drive's control board. I have seen posts here before that have this symptom - large disk appears to be only 32 MB - and the problem is that the HDD has failed entirely, and the system only sees the buffer RAM on the disk's board.
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a c 127 G Storage
July 28, 2009 7:39:07 PM

LOL i never heard you could store data directly on the DRAM memory chip.

I have heard about a jumper that limits the capacity of the drive. My old hitachi still has this, in the time 28-bit LBA was common. So check if your jumpers are right, maybe you put one at the wrong position. :) 

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a c 349 G Storage
July 29, 2009 9:48:00 PM

When a drive malfunctions and your system is able to detect only 32 MB of "drive space", I doubt you can actually write to it or read from it. Anyway, why would you if you could? It will all disappear when powered off, because this is only DRAM, not magnetic records.

The original version of LBA, now named "28-bit LBA", allowed the system to specify the address of a data block on the hard disk by a simple single number ranging from 0 to a max, rather than a combination of Cylinder, Head No. and Sector. The HDD unit's on-board controller translates from sequential number to CHS co-ordinates, among its many jobs, and finds what you want. In the initial version of LBA, 28 binary bits were used to define that sequential number, so the maximum number of the last addressable block was (2^28)-1, which is 268,435,455. Now the standard block contains 512 bytes, so the maximum capacity you could address in this system is 137,438,953,472 bytes - hence the disk manufacturer's version of the limit, 137GB. Microsoft, on the other hand, uses the term "GB" to mean 1024 * 1024 * 1024 bytes, so they call this limit 128 GB.

The newer version of LBA implemented around year 2000 uses 48 binary bits to define the block number, so now the maximum capacity addressable is 144,115,188,075,855,872 bytes, or a bit over 144 Million GB, and we won't get there soon.

Note that nowhere in here is there a 32 MB or 32 GB limit. If your disk is detected at 32 MB, it is NOT because of 28-bit old-style LBA.

Some hard drive makers used a jumper system to limit their larger drives to no more than 28-bit LBA can use. That is just a way to ensure such a drive can be forced to be compatible with older systems. But the result is still that the drive set that way has a capacity of 128 GB, not 32 GB or 32 MB.

There's another way the 32 GB number can come up, if it really is GIGAbytes. If you chose to Format your drive with the older FAT32 File System, its fixed FAT (File Allocation Table) structure (if it uses common Microsoft Allocation Unit size) will limit you to 32 GB of capacity. If that is the case, the solution is to back up any data you have on there already, then Delete all Partitions on the drive, then create on it a new Primary Partition that uses all of the drive and Format that Partition to use the NTFS File System. Then you can use the whole drive.

Oh, the other solution is to stay with the FAT32 File System, but then you have to create on your drive about 5 separate Partitions, each formatted to FAT32, and each treated by your system as separate drives with their own drive letter names.
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a c 127 G Storage
July 29, 2009 9:51:43 PM

I could fine only this:

Quote:
Clip to 33 GB

A more recent limit is the 33.8 GB limit. Linux kernels older than 2.2.14 / 2.3.21 need a patch to be able to cope with IDE disks larger than this.

With an old BIOS and a disk larger than 33.8 GB, the BIOS may hang, and in such cases booting may be impossible, even when the disk is removed from the CMOS settings.

Therefore, large IBM and Maxtor and Seagate disks come with a jumper that make the disk appear as a 33.8 GB disk. For example, the IBM Deskstar 37.5 GB (DPTA-353750) with 73261440 sectors (corresponding to 72680/16/63, or 4560/255/63) can be jumpered to appear as a 33.8 GB disk, and then reports geometry 16383/16/63 like any big disk, but LBAcapacity 66055248 (corresponding to 65531/16/63, or 4111/255/63). Similar things hold for recent large Maxtor disks.


http://www.win.tue.nl/~aeb/linux/Large-Disk-11.html
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