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Vintage Computers Any vintage computer systems, calculators, video games etc., but with an emphasis on 1980s and earlier equipment. |
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24th Jul 2020, 5:42 pm | #21 | |
Administrator
Join Date: Dec 2002
Location: Cardiff
Posts: 9,071
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Re: Hard drive erasing?
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A good indication is to look on eBay and see how many of them are being offered for sale, and what sort of prices the sold ones are fetching. Anything that is on there in large numbers and selling for under a tenner is not worth wasting time with. Unless someone wants to store then for 10-20 years and see if they are worth anything then? However older MFM etc interface drives and indeed any where the capacity is shown in Megabytes rather than Gigabytes are definitely not in that category. With the drives being discussed here it may be worth checking how common they are now before reaching for the hammer. |
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24th Jul 2020, 6:05 pm | #22 | |
Nonode
Join Date: Aug 2010
Location: Resolven, Wales; and Bristol, England
Posts: 2,608
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Re: Hard drive erasing?
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24th Jul 2020, 6:25 pm | #23 |
Heptode
Join Date: Feb 2010
Location: Heysham, Lancashire, UK.
Posts: 668
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Re: Hard drive erasing?
At one time, I worked for a company with some customers who would not let failed hard drives off their site unless they had been turned into fine granules. They wouldn't let DRAM boards off their site either, DRAMS don't guarantee to forget everything after the refresh time is exceeded, the repair person could unplug them from the computer and surreptitiously quickly plug them into something else to preserve the contents.
To avoid scrapping major bits of the hardware, I once had to explain that I would stake my life that a large board of ECL logic containing ECL SRAMs would forget everything pretty quickly once the power was off. Quite different to the earlier core stores, which had significant long term memory of you talked to them nicely - the core was definitely not allowed off site. The concern was that baddies who knew where the parts came from would go to considerably lengths, and plenty of time and money, to extract fragments of information. With the business some of them were in, they were right to be paranoid, but I wouldn't think such precautions were needed for folk on here with old household computers. Would reformatting the drive be enough to hide such things as bank passwords from almost anyone except highly specialized agencies? Stuart |
24th Jul 2020, 6:37 pm | #24 |
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Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,943
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Re: Hard drive erasing?
No. You need to overwrite the data. Reversing a disk format is relatively easy if somebody wants to do it - you don't need to be James Bond, or even a data recovery specialist.
Overwriting the disk is very straightforward though - it just takes a while with a big drive as every disk block needs to be rewritten. |
24th Jul 2020, 7:10 pm | #25 |
Heptode
Join Date: Jul 2016
Location: Portland, Dorset, UK.
Posts: 874
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Re: Hard drive erasing?
I have just always used a PC and Darik's? Boot And Nuke (DBAN), will run even off a floppy.
Choose a method that's thorough enough for the sensitivity of the data that's on it and let it get to work. https://dban.org/ |
25th Jul 2020, 9:19 am | #26 | |
Octode
Join Date: Jul 2009
Location: Carmel, Llannerchymedd, Anglesey, UK.
Posts: 1,507
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Re: Hard drive erasing?
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25th Jul 2020, 10:04 am | #27 |
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Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,943
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Re: Hard drive erasing?
Yes, this is a theoretical technique which has been demonstrated in the lab with very small amounts of data. A custom firmware board is used which allows the position of the heads to be deliberately slightly misaligned. The resultant signal is then subjected to lots of digital processing which in some cases can decode the overwritten data, though the error rate is high and the techniques have more in common with statistical cryptography than normal data recovery.
Nobody has ever publicly demonstrated recovering a complete overwritten real world disk using this technique. People like the military and GCHQ have to consider attacks by state actors with unlimited resources, so adopt an extremely conservative approach. The 'bash it with a hammer' method advocated in this thread wouldn't be good enough in these circumstances, as data can be recovered from physically damaged platters given sufficiently advanced facilities. |
25th Jul 2020, 10:33 am | #28 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,998
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Re: Hard drive erasing?
A friend of mine gives his scrap HDDs a "Makita Format" - drilling a dozen holes right through the entire thing - PCB, chassis, platters, cover - with a 10mm drill.
I have been known to lob smaller HDDs into my woodstove, where they are reduced to grey 'slag' in an hour or two. |
25th Jul 2020, 11:36 am | #29 |
Heptode
Join Date: Feb 2010
Location: Duffort, Gers, France
Posts: 714
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Re: Hard drive erasing?
If the machines won't boot up then I don't see any easy way to erase them in situ. Boring holes in them is as good a way as any to render them unreadable. However if you remove them then why destroy them? A buyer won't be interested in a destroyed drive so you'll be selling the Macs without drives anyway. Just keep the drives somewhere. You can always connect them to an adapter which converts them to a USB drive. Then you can easily plug them into any PC you want if you suddenly realise that you need the data on them after all, or run some erasing software (on Linux dd works very well).
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Stuart The golden age is always yesterday - Asa Briggs |
25th Jul 2020, 1:35 pm | #30 |
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Re: Hard drive erasing?
In the dim and distant past I was involved with Mil spec. laptops, some had a marker to show where to aim a gun to destroy the HDD. Effective but unlikely to be available to most of forum members.
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25th Jul 2020, 1:47 pm | #31 |
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Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,943
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Re: Hard drive erasing?
That would make sense for laptops used in combat zones, where withdrawing forces might need to destroy data quickly without any special skills. You don't want to mess about booting Linux from a CD when the Islamic State fighters are coming over the hill.
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25th Jul 2020, 1:47 pm | #32 | |
Dekatron
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,642
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Re: Hard drive erasing?
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25th Jul 2020, 2:04 pm | #33 |
Rest in Peace
Join Date: Jun 2006
Location: Chard, South Somerset, UK.
Posts: 7,457
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Re: Hard drive erasing?
Whenever I've decided to scrap an HDD, it's reach for the set of Torx drivers, dismantle the drive, remove the platters and using a power saw, cutting them in half. Often I keep the magnets. They're useful for attaching 'post-it' type notes on the 'fridge door: "The milk lives in here!" etc.
Al. |