Folkert Rienstra <see_reply-(E-Mail Removed)> wrote in message
news:42bcab88$0$35661$(E-Mail Removed)...
> Rod Speed <(E-Mail Removed)> wrote
>> Folkert Rienstra <see_reply-(E-Mail Removed)> wrote
>>> Rod Speed (E-Mail Removed)> wrote
>>>> Folkert Rienstra see_reply-(E-Mail Removed)> wrote
>>>>> Ben Bradley (E-Mail Removed)> wrote
>> > > > > I'll ask the question I can get an answer for first, and describe
>> > > > > the background/rant/how it happened further down.
>> > ...
>> > > > > Several days after moving the monitor I ran scandisk on one drive and
>> > > > > was surprised to see a LOT of bad blocks, and I ran it on the other
>> > > > > drive and saw many bad blocks on it as well.
>> > ...
>> > > > > I moved the monitor away and ran scandisk on each drive a
>> > > > > couple more times, and a few more marginal "adjacent blocks" were
>> > > > > detected as bad each time, but these are a small number (maybe 10-20)
>> > > > > ...
>> > > > > After some googling for disk utility programs, I downloaded and
>> > > > > ran
>> > > > > diagnostic programs from Western Digital and Maxtor.
>> > ...
>> > > > > On the machine in question they can read the SMART data, but of
>> > > > > course find enough errors on full disk scan to say "This drive is
>> > > > > failing."
>> >
>> > > > > I had one utility do a "write zeros" to Drive D: (the 80 gig), did
>> > > > > an FDISK to reestablish it as a DOS drive, then did a DOS/Windows
>> > > > > Format to clean it off and put a filesystem on it. Running scandisk
>> > > > > on
>> > > > > this just ends up rediscovering all the bad blocks that it had found
>> > > > > before (all the B's are showing up in the same place as before on
>> > > > > this
>> > > > > drive). Currently scandisk shows out of 2,441,533 clusters, 427,000
>> > > > > examined, 670 found bad.
>> > > >
>> > > > > I've read about 'spare tracks' (drives internally have
>> > > > > substantially more storage than advertised, and use this space to
>> > > > > invisibly replace failing/marginal tracks), but I don't know of a way
>> > > > > to tell how many of these are actually being used in a 'perfect'
>> > > > > drive. I presume there's some utilities to show total spare tracks
>> > > > > and
>> > > > > how many are in use - what program does that? (not that it would help
>> > > > > me here, this is just general interest)
>> >
>> > > > > Apparently all the 'spare tracks' on these two drives are all used
>> > > > > up.
>> >
>> > Maybe, maybe not. S.M.A.R.T. should be able to tell.
>> >
>> > > >
>> > > > > These errors on the disk are apparently 'soft' in that they are
>> > > > > caused by bad data written to the disk, and not by bad media itself,
>> > > >
>> > > > Apparently not, in your case.
>> > > >
>> > > > > so if these areas could be rewritten, these spots could be fixed.
>> > >
>> > > > You've done that. From what you're saying, it didn't resolve the
>> > > > problem.
>> > > > Apparently the spots are weak.
>> > >
>> > > Impossibly unlikely that that many would all go weak at once.
>>> First, it aren't that many
>> FAR too many to all go weak at once.
> Not if the monitor caused that.
Have fun explaining you previous pig ignorant claim that there arent that many.
Not a clue, as always.
And what the monitor did doesnt qualify as 'weak' either.
>> And have fun explaining
>> > > > was surprised to see a LOT of bad blocks, and I ran it on
>> > > > the other drive and saw many bad blocks on it as well.
>> > > > I at first thought an electrical spike might have caused this, but
>> > > > then I observed that it corresponded to moving the monitor next to the
>> > > > machine. I moved the monitor away and ran scandisk on each drive a
>> > > > couple more times, and a few more marginal "adjacent blocks" were
>> > > > detected as bad each time, but these are a small number (maybe 10-20)
>> > > > compared to the first time I saw the problem (hundreds).
>>
>> > > > Currently scandisk shows out of 2,441,533
>> > > > clusters, 427,000 examined, 670 found bad.
>>
>> You aint gunna see 670 go weak all at once.
>>
>> > and second, if it was so bad what supposedly has happened
>> > one would actually expect much much more gone bad.
>>
>> Pathetic, really.
> Yes, you are.
Pathetic, really.
>>> What likely has happened is that the lesser areas,
>>> that were good enough previously, have worsened
>>> under the influence of the monitor and now are failing.
>> Have fun explaining the physics of that.
> *You* have fun explaining a different cause.
The monitor just damaged some headers, fool.
>>> Since data is rewritten and therefore should be as good as
>>> new it is likely the Servo info or the Low Level Format detail,
>> You mean the headers.
> Wot headers.
> There are no headers anymore on recent drives, stupid.
There are on those two drives he saw that problem with, ****wit.
> I said 'Servo info' or 'the Low Level Format detail', the latter being
> what is left from what formerly was the Sector ID header. Most of
> that is now in silicon and is not affected by magnetic interference.
> What is still left there in the tracks that isn't particularly Servo info,
> that is what I meant.
Pity you garbled it so comprehensively, as always.
>> > that *doesn't* get rewritten, that's causing the misreads.
>>
>> > > > > I looked up low-level formatting in hopes of doing that,
>> > > > > and it's clear that you can't low-level format modern drives.
>> > >
>> > > > No, that is not clear. Not that it matters. The sparing system
>> > > > is in essence a LLF on the single sector level. Writing zeroes
>> > > > to bad sector candidates is doing a selective LLF.
>> > >
>> > > Its more complicated than that if what appears to be
>> > > bad varies due to that being due to external factors.
>>
>> > Read the post again.
>>
>> No need.
>>
>> > On the first run he found many that then were taken out of service
>> > as far as scandisk is concerned. Consecutive runs then found only a
>> > few extra that weren't found the first time. Then he zeroed the drive
>> > and scandisk checked all clusters again and found all the bad ones again.
>>
>> No news.
>>
>> > That is to be expected *IF* the spots are weak
>> > (ie not really bad enough to be replaced).
>>
>> You aint gunna get 670 all go weak at once.
> Yes you do if that monitor has anything to do with it.
Nothing to do with 'weak', fool.
>> > If the spots are really bad they shouldn't reappear
>> > after a 'zero' action unless the replacements are
>> > also bad (or weak), or the drive is out of replacements.
>>
>> Or its the sector headers that got damaged by the monitor
>> and those weren't affected by writing zeros to the drive.
> That wot I said, clueless.
Lie, as always, ****wit.
>> > > > > And so, these drives were made pretty much FUBAR just by putting a
>> > > > > running CRT monitor next to the PC case for a few days. Is it common
>> > > > > knowledge that this can happen? I'm really surprised I haven't heard
>> > > > > about it. I didn't even think of possible drive damage when I put the
>> > > > > monitor there. Hard disk drives are put next to rotating fans and
>> > > > > switching power supplies very often, and those things generate
>> > > > > magnetic fields, and are supposed to have high coercivity and be
>> > > > > difficult to erase. Perhaps long-term they DO cause errors in hard
>> > > > > disk drives, and no one has noticed or tied it to adjacent devices
>> > > > > creating magnetic fields.
>> > > > >
>> > > > > I can already hear the responses "go buy a new computer, they're
>> > > > > cheap enough..."
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