Category: hard disk

PENDING SECTOR COUNT

Ordinarily hard disks operate transparently. Any problems are handled by the drive logic. Disks in use may find problem sectors or tracks and they then map spare area into the block number table when the error correction cannot cope. badblocks -sv -b 512 <device-name> If the disk is one of the newer 4K sector designs, …

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COMMON HARD DISK PROBLEMS

Forums are full of posts with people inquiring about a disk that is not working. One of the most common problems is due to BIOS errors. Its advisable to use BIOS defaults and only select AHCI for modern hard disks only. Even modern UEFI boards default to IDE for legacy operating systems. If the hard …

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4K SECTORS

Historically hard disks used 512 byte sectors. Early hard disks had very few sectors on a track so it was considered a good compromise at the time. Over time, however, disk capacity grew exponentially to the point where the number of sectors on a track became unwieldy. Seagate and WDC both adopted the move to …

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OUR SATA DISKS

SATA disks were introduced in 2005 with the Intel D915PGN desktop motherboard. SATA use 7 data pins while SAS use 14 data pins. Both use 15 power pins. The SFF-8482 connector makes it possible to connect disks to a backplane to simplify replacement. SATA DISK RELIABILITY OPERATING HOURS Remember there are 8,760 hours in a …

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FIX HARD DISK CLICKING

First off you should own lots of disks so that redundant copies of important data does not get lost. This guide is not an easy solution and a disk may be wiped when repaired. The clicking sound is generally caused by a faulty logic board. Replacing the logic board requires the exact make and model disk …

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FAILED HARD DISKS

Every data center has had it fair share of disk failures. So far we have experienced very few disk failures. Clicking sounds, for example, indicate that the head is seeking back and forth and the disk does not present to the BIOS etc. We experienced 2 failures with 500GB disks arising from changes in soldering. The …

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OUR EIDE DISKS

ATA disks, later called EIDE, were introduced in 1985 with a lower cost controller board. The control logic was moved to logic board on the disk assembly which free manufacturers to design new products more easily. The 40-pin cable was eventually replaced with an 8-conductor wire to allow for higher speeds. EIDE hard disks are …

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BAD SECTORS

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In the early days of hard disks, manufacturers placed bad sector tables on the labels of the disks. This was done so that manual marking of bad sectors could be done. The image shows an old MFM  hard disk with its defect table. This was typical of early hard disks. MS-DOS formats disks completely and …

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HARD DISK SURVIVAL

Almost everyone has had disk errors at one time or another. There are the file system errors but this page is concerned with mechanical failures of hard disks. We purchase hard disks frequently primarily to take advantage of capacity increases. The photo is the ST-506 5MB hard disk ($1,500) that was the less expensive of …

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