Bad sectors on a hard drive....low level format?

[zippy]

My sister's friend's laptop has bad sectors and is dying. I am gonna install her hard drive on my computer to save what files she needs then do a fresh install.

I will need to do a low level format to fix these bad sectors, right? Or is there no repair for bad sectors...

I said I was gonna do a low level format to save it, but then I just got to thinking and wanted to make sure.

Thanks.

 

[Gatsby]

I remember from the screensavers that a low level format is VERY hard to do and is VERY dangerous to do. Its possible to do it but if you f up good bye drive. its off to HD heaven.

I believe if you can get it RMAed but it might be too old or just look for a new HD to install.

Corrections appreciated. (this is off the top of my head)

Gatsby

 

[RSI]

Just make sure you are using the appropriate software (ex, Disk Manager) to do so.

 

[Eli]

I dont think you can fix bad sectors ..

 

[BigToque]

How is a low level format "dangerous" to do? All it does is write zero's to the drive right?

I had a drive that windows was screwing up on, and scandisk marked almost every single sector as a bad sector (would have if I didnt reboot). I then hooked the drive up to my old system that had a low level format in the bios, did the format and reinstalled windows, and its been running fine for 2+ years.

 

[Budman]

Doing a Low level format will remove the bad blocks.

But they will return,the drive is physicaly dammaged & can not be repaired.

RMA is your only solution.

 

[zippy]

Ok, this is still under warranty from Gateway. I will tell her that she is best off getting the data she needs and putting it onto my computer and then RMAing it at the local Gateway country because the drive is physically damaged and the problem will probably return, the LLF will help but not completely repair and since it is under warranty she should just RMA it.

 

[dszd0g]

Doing a low level format will remove all the sectors that are marked bad. They are still bad, you would have just remarked them good. Modern drives reserve some of its space with bad sector allocation tables. By the time you as a user see bad blocks a significant portion of your disk is trashed. In the old days of computers MFM and IDE drives did not have the allocation tables while SCSI did which contributed to earlier improved reliablity with SCSI. Now both SCSI and IDE have it. However, if you are seeing bad blocks the drive is toast. Recover what you can and then replace the drive.

 

[Howard]

What Budman and dszd0g and Eli and Gatsby said.

 

[Hector13]

Can you even take the hard drive out of the laptop and install it on your pc?

At the very least I think this would void the warranty on the laptop.
Anyway, I think your best bet is RMA

Good luck

 

[schlongdaddy]

take the system to a local GW country store and tell the service dept the HD is going bad, they will run a program called 'GWSCAN' which will check the drive for all types of error (it works very well)

If an error is found they will replace the drive and install the original software that came with the system, that is if the laptop is still in warranty, system will probably be down for 1 or 2 weeks

 

[zippy]

They said she had to wipe clean and reinstall. I just thought I could cut her time w/o her computer down.

I can take out a laptop hard drive (have before...my friend's old toshiba) and install it in my computer (ide is ide...) then take her stuff, but it back all nice and tell her to take it to gateway cuz it is going, going, almost gone!

 

[LevcoS]

If I were you, I'd give SpinRite a try before doing anything else.

http://www.spinrite.com

LevcoS

 

[12Guage]

Contrary to popular opinion, doing a low level format is not bad for your hard disk, any more than flashing your bios is bad for your bios. All it does is rewrite the cylinder, head, sector info. Just be sure you use the manufacturers LLF utility for your model. LLF will remap any bad sectors to good ones in reserve so you cannot write to them anymore.

Somtimes a "bad" sector is not really bad, just sort of stuck. A utility like Spinrite could recover those "bad" sectors.

Even a simple scandisk surface scan (run from a Win9x boot disk) will mark bad sectors and Windows will not write there anymore. It can even recover your data (sometimes) from bad sectors.

Just be sure to back up your sister's friend's data before you LLF her disk

 

[Jhhnn]

Doing a RMA seems like good advice, why mess with it when it's Gateway's problem? Spinrite has a good reputation, although I've never used it myself. Several (all?) HD manufacturers offer free product specific downloadable disk utilities, the ones from seagate and western digital have worked well for me, and are easy to use.

 

[Aboroth]

The people who say that low level formatting always just marks bad sectors good are wrong. 12Guage is right. Sometimes bad sectors are not physically damaged, but they are just corrupt and marked bad by a disk checker. A low level format will fix these. I have had this happen to me before. A virus screwed up my Fireball KA and low level formatting got rid of the bad sectors, never to return even after many scandisk checks. However, don't do it with your BIOS. Every good HD manufacturer has a utility to do this for you, specifically written for their drives. You can get it from their web site.

 

[Aboroth]

Quantum can explain it better than I can. Here is a link to their page explaining bad sectors.
http://www.quantum.com/app_notes/app_note_ata_badsector.htm

There are two situations that will cause a drive to develop bad sectors. One situation is when corrupted data is stored on the drive; the other is when physical damage has occurred inside the unit.
Corrupted Data: This is known as a logical error and is correctable. We recommend using our Zero Fill utility, which will write zeros to the entire drive, returning the drive to a "like new" condition. After running the Zero Fill utility you will need to partition the drive and format it, since the utility will remove this information, as well as the data.

Physical Damage: Physical damage of the unit is uncorrectable. Shipping or handling damage is usually the cause of this type of damage. If the drive has physical damage it will have to be replaced.

 

[dszd0g]

To the best of my knowledge if you LLF a drive it will mark bad sectors good whichever way they are caused. I could see in Aboroth's situation where a virus falsely marked sectors bad that a LLF would help. However, most of the time bad sectors are actually caused by a drive going bad. If the drive is going bad the bad sectors will return. I agree that as long as you use the manufacturer's LLF utility it should not harm the drive. In my experience the SCSI LLF seems to be standardized so any decent SCSI card's BIOS should be able to LLF. I would not format from the main BIOS for IDE drives I have heard of this trashing drives before. Most manufacturers have a utility for LLF IDE drives. However, if your drive is going bad I don't see how doing a LLF will help anything either.

 

[Edski]

The truth about LLF is that with the newer drives out today is that they will not work on drives that are not they are not intended for. In older drives that is a different story. That problem is the interleave (sp), if you run an LLF with a different interleave than what is on your drive, you will ruin the drive, plain and simple.

 

[StanTheMan]

Try to fdisk your hard drive instead of low format. if the bad sector is not caused by physical damage, teh will disappear. WARNING: FDISK WILL ERASE ALL OF YOUR DATA

 

[Mark R]

No drive made in about the last 6 years (and probably a lot longer than that) can be low level formatted in the way that 12gauge describes.

All that a LLF does these days is just wipe all the information on the drive. This includes windows' bad sector list. As a result all the bad sectors are marked as good again.

This is not necessarily a bad thing (for example if you are plagued by the 'logical' errors, as described by Quantum).

However, it does hide real bad sectors. These are then free for windows to store you files, and in my experience will end up trashing your data.

 

[12Guage]

Whoa guys, some major missinfo about Low Level Formating going on here. Lets set the record straight. K?

3 steps involved in preparing a hard disk after it leaves the assembly line.

1: Low Level Format LLF is a "real" format, the tracks and sectors info of the disk are outlined and data is written across the entire disk.

2: Partioning. Use fdisk, Partion Magic or whatever tool you like. The Master Boot Record is created and partition info is written to the disk.

3: High Level Formatting. Use the format command in dos. Main purpose is to create a fat.

A Low Level Format does several things to your disk.
- it scans for existing defect mappings
- it selects the proper interleave
- it formats and marks defects
- it runs a surface analysis

In the "good' ole days, 5 or 6 yeas ago, of 100 meg hard disks, when you ran an LLF on a hard disk the LLF utility required a lot of user intervention. Now a days, the manufacturers LLF utility does all this for you. All you gotta do is hit "Y" when it asks you if you want to LLF the drive.

Make no mistake, any LLF util today still does this. Track and sector info is written to the disk and any bad sectors are marked and remapped to good ones. The rest of the drive is zero'ed. Zeros are written to all available sectors, making any previously stored data unrecoverable. "Unformat" won't work after you LLF.

Marking and remapping bad sectors with LLF makes bad sectors invisible to dos. As far as dos or Windows is concerned, a freshly LLF'ed disk will have "Zero bytes in bad sectors" no matter how many times you Fdisk, Format and scandisk surface scan.

Using scandisk to mark bad sectors writes bad sector info to the fat.
As soon as you wipe out the fat with Fdisk of Format, your bad sectors will reappear.

I think there is some confusion here between the format command in dos
and a Low Level Format tool like Maxtor's MaxLLF.

 

[zippy]

Yeah, I'm not a fscking retard. I have built computers, fixed em, etc. So I know how to do a damn fdisk and format and have used partition magic on my own machine.

I know what a LLF does (writes "0"'s to every bit)...my only question is this (a direct quote from the beginning):



<< I will need to do a low level format to fix these bad sectors, right? Or is there no repair for bad sectors... >>



Sorry if I sound ungrateful for your help, but no one has actually helped me because everyone says the other person is wrong and some of you are talking down to me like I'm a newbie.

Stan:

<< WARNING: FDISK WILL ERASE ALL OF YOUR DATA >>

...<sarcasm>NO WAY?!?!?! Sh!t, so you mean I won't get all my pr0n and metallica mp3s back now? Awwww crap...</sarcasm>

 

[12Guage]

Sorry about that zip, K. To answer the question. NO LLF WILL NOT REPAIR PHYSICALLY BAD SECTORS.

What LLF will do is write an invalid checksum to each physically damadged sector and stick in a pointer to a good sector located on a reserve track. A sector marked in this way is ignored by dos when it's writing out the File Allocation Table durring the high level format and dos will use the good sector instead. This is why bad sectors dissapear after you LLF your disk.

The bad sector stil exists but is not used or written to, for all intents and purposes it's been replaced by a good one.

Bad sectors marked by scandisk that only have logical errors are recorded in the fat. These sectors are recovered when LLF destroys the fat and zero's the disk, overwritting any logical errors with a zero.

What most people don't realise is that most hard disk drives leave the assembly line with some bad sectors. It's the Low Level Format done by the manufacturer that &quot;removes&quot; them.

 

[zippy]

Thanks 12, so basically, I could give LLFing a shot as it probably will help, but if there are any more sectors that go bad...the drive is dead.

I'll tell her this, confuse the hell outta her and tell her she should have it replaced by Gateway.