Bad Sectors

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Sep 17, 2020
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London UK
I am getting BSOD on my old laptop, so I thought I would run 6.1 on Level 5. It is a 2.5 spinning 750GB. I am getting 15 Black B's (31 sectors) in the first 5.2% of the drive, this is something I have not come across before, I have had both the R & U in the past but never the B. Does this mean the data that was in them has been lost, or Spinrite has recovered what was there and moved it to a readable sector. As I said this is an old drive (13 years) so maybe it is at EOL.
 
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Black B's
I believe this means they're sectors the drive has already marked as bad, so it already found there was a problem with them in the past and dealt with it, or else reported it to the OS for it to deal with. Depending on how they were dealt with the data was already lost or relocated.
 
I believe this means they're sectors the drive has already marked as bad
If they were already marked as bad, surly Spinrite would pass over them (or not even display them) and not spend time trying to rearranging the data. This seems to be a very troubled drive, I am now getting loads of command time outs, relocated sector, ECC errors on a second attempt on level 3 (because it is quicker than 5). Funny, this time no bad sectors were found on the first 5% of the drive.

But I am now getting in the log "The drive has refused to rewrite original data. Attempting rewrite to identify unwritable sector (s)." & "After a minor problem reading this sector occurred and a repeated attempt succeeded, this sector has been re-written." Also I have never seen before, in the SMART display is 2 red squares under "pending sectors" (74/77). The same in "uncorrectable" What does that mean?

The laptop has been getting slower & slower even after running Spinrite, like I said I think the drive may be EOL (end of life). I would like to replace the drive, and reinstall to the two OS's to see if there is any improvement, but as this is a old laptop which I have replaced both the screen & keyboard over the years, I do not want to spend a further £50-100 to find out. BTW, I believe it is a Seagate ST9750420AS.
 
The laptop has been getting slower & slower even after running Spinrite, like I said I think the drive may be EOL (end of life). I would like to replace the drive, and reinstall to the two OS's to see if there is any improvement, but as this is a old laptop which I have replaced both the screen & keyboard over the years, I do not want to spend a further £50-100 to find out. BTW, I believe it is a Seagate ST9750420AS.
@Mervyn Haynes

It does indeed sound like this old Seagate drive is dying and desperately needs to be replaced. A new healthy drive would be very noticeably faster and the system would be expected to also be noticeably faster. Whether that is worth it to you for this old system is a judgement call only you can make.
 
Whether that is worth it to you for this old system is a judgement call only you can make.
Yeah, I have looked on ebay, and the cheapest I can get one for is £13-25, but that is from China, and I think it would be a fake, ie have a SD card inside! I think this old lady is bound for retirement. So, do we really know what happens to the data in the sectors Spinrite has worked on and marked as bad?
 
@Mervyn Haynes , any 2.5” SATA drive would work, right? You don’t need the same model. At least in the US, you can get a cheap SSD for $25.

 
@Mervyn Haynes It does indeed sound like this old Seagate drive is dying and desperately needs to be replaced. A new healthy drive would be very noticeably faster and the system would be expected to also be noticeably faster. Whether that is worth it to you for this old system is a judgement call only you can make.

I agree, it sounds like the drive is "snowballing" into a full-on crash of the platters....
 
So, do we really know what happens to the data in the sectors Spinrite has worked on and marked as bad?
When a sector can no longer be reliably read from or written to, i.e is bad, the data that was there is likely lost. :)

If some data had been recovered, that would have been written to a new sector when the bad sector was reallocated.
 
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Thanks for all your suggestions. I thought this was an old PATA drive, but on opening the laptop up it is a SATA. Looked on ebay and i can get a Seagate 1Tb for £28! So I think I will go down that route.
One again thanks to all.
 
Thanks for all your suggestions. I thought this was an old PATA drive, but on opening the laptop up it is a SATA. Looked on ebay and i can get a Seagate 1Tb for £28! So I think I will go down that route.
One again thanks to all.
Strongly recommend getting an SSD if you can live with the lower capacity per £.
 
Strongly recommend getting an SSD if you can live with the lower capacity per £.
Thanks Scott, I did think of that, but this is only a reserve laptop in case my main one fails. So it will only be used very rarely, & for Spinrite testing, as my main laptop is UEFI only.