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Spinrite may "write" 00000000 to a specific location on the disk, but that 00000000 is actually encoded as something else when it is written to the disk to maintain a minimum number of bit transitions. In the Telecom world, B8ZS is commonly used for encoding. AFAIK, the HDD manufacturer's algorithms are proprietary.

It is also worth mentioning that a hard drive head does not read a binary signal from the platter. It reads an analog waveform and converts it to digital via the encoding and ECC algorithms the OP is trying to bypass.

-ellie

Scott Moulton of http://myharddrivedied.com/ is the smartest HDD guy I know. If you absolutely have to have a solution, talk to him.

Quoted from here:

Spinrite is not data recovery software. I get many questions about why I left off Spinrite on my recommendations of recovery software. I specifically leave off Spinrite because under the strictest terms it is not data recovery software. Almost every single data recovery package knows, and will warn you not to write the data back to the original source drive. Data Recovery/Forensics software almost always recover from a source to a destination. Spinrite does not do that, it refreshes the surface and controls reads to get the maximum amount of data from the sectors and then puts it back down on the same drive.

I think it does quite a few things very well and it does an excellent job at reporting and reading the SMART info and refreshing the surface of the hard drive. However, I would like to first try to get the data from the drive before scanning it and trying to rebuild sectors. There are many reasons for this, but the most important one being that the drive can die in the process of running Spinrite. It is possible to do more damage to the drive by doing excessive read and writes. There are times that you only get once [sic] good chance at data and if you use a tool that just goes in and surgically removes the data you want BEFORE doing the scan you will be a lot safer.

If I was going to use Spinrite, I would get everything I could off the drive to another destination first and then use Spinrite to try to get anything I could not repair (although I never have to with the tools I use). Another horrific story I have seen with drives sent to me, is that if Spinrite it runs successfully, people are under the impression that the drive is repaired and is usable again and continue to use it. Big mistake and it usually dies again shortly. On a Windows Hard Drive I would try NTFSExplorer/FatExplorer first in the hopes of doing a surgical recovery as oppose to spending days rewriting sectors in the hopes that my drive can live though it as Spinrite does. But for $80 it is well worth the attempt if you are going to do nothing else. Good Luck.

Oct 6, 2008 11:26 PM ~ Scott A. Moulton

Also, you can find some very interesting papers/presentations/videos here.

Quoted from here:

Spinrite is not data recovery software. I get many questions about why I left off Spinrite on my recommendations of recovery software. I specifically leave off Spinrite because under the strictest terms it is not data recovery software. Almost every single data recovery package knows, and will warn you not to write the data back to the original source drive. Data Recovery/Forensics software almost always recover from a source to a destination. Spinrite does not do that, it refreshes the surface and controls reads to get the maximum amount of data from the sectors and then puts it back down on the same drive.

I think it does quite a few things very well and it does an excellent job at reporting and reading the SMART info and refreshing the surface of the hard drive. However, I would like to first try to get the data from the drive before scanning it and trying to rebuild sectors. There are many reasons for this, but the most important one being that the drive can die in the process of running Spinrite. It is possible to do more damage to the drive by doing excessive read and writes. There are times that you only get once [sic] good chance at data and if you use a tool that just goes in and surgically removes the data you want BEFORE doing the scan you will be a lot safer.

If I was going to use Spinrite, I would get everything I could off the drive to another destination first and then use Spinrite to try to get anything I could not repair (although I never have to with the tools I use). Another horrific story I have seen with drives sent to me, is that if Spinrite it runs successfully, people are under the impression that the drive is repaired and is usable again and continue to use it. Big mistake and it usually dies again shortly. On a Windows Hard Drive I would try NTFSExplorer/FatExplorer first in the hopes of doing a surgical recovery as oppose to spending days rewriting sectors in the hopes that my drive can live though it as Spinrite does. But for $80 it is well worth the attempt if you are going to do nothing else. Good Luck.

Oct 6, 2008 11:26 PM ~ Scott A. Moulton

Also, you can find some very interesting papers/presentations/videos here.

Quoted from here:

Spinrite is not data recovery software. I get many questions about why I left off Spinrite on my recommendations of recovery software. I specifically leave off Spinrite because under the strictest terms it is not data recovery software. Almost every single data recovery package knows, and will warn you not to write the data back to the original source drive. Data Recovery/Forensics software almost always recover from a source to a destination. Spinrite does not do that, it refreshes the surface and controls reads to get the maximum amount of data from the sectors and then puts it back down on the same drive.

I think it does quite a few things very well and it does an excellent job at reporting and reading the SMART info and refreshing the surface of the hard drive. However, I would like to first try to get the data from the drive before scanning it and trying to rebuild sectors. There are many reasons for this, but the most important one being that the drive can die in the process of running Spinrite. It is possible to do more damage to the drive by doing excessive read and writes. There are times that you only get once good chance at data and if you use a tool that just goes in and surgically removes the data you want BEFORE doing the scan you will be a lot safer.

If I was going to use Spinrite, I would get everything I could off the drive to another destination first and then use Spinrite to try to get anything I could not repair (although I never have to with the tools I use). Another horrific story I have seen with drives sent to me, is that if Spinrite it runs successfully, people are under the impression that the drive is repaired and is usable again and continue to use it. Big mistake and it usually dies again shortly. On a Windows Hard Drive I would try NTFSExplorer/FatExplorer first in the hopes of doing a surgical recovery as oppose to spending days rewriting sectors in the hopes that my drive can live though it as Spinrite does. But for $80 it is well worth the attempt if you are going to do nothing else. Good Luck.

Oct 6, 2008 11:26 PM

Also, you can find some very interesting papers/presentations/videos here.

Quoted from here:

Spinrite is not data recovery software. I get many questions about why I left off Spinrite on my recommendations of recovery software. I specifically leave off Spinrite because under the strictest terms it is not data recovery software. Almost every single data recovery package knows, and will warn you not to write the data back to the original source drive. Data Recovery/Forensics software almost always recover from a source to a destination. Spinrite does not do that, it refreshes the surface and controls reads to get the maximum amount of data from the sectors and then puts it back down on the same drive.

I think it does quite a few things very well and it does an excellent job at reporting and reading the SMART info and refreshing the surface of the hard drive. However, I would like to first try to get the data from the drive before scanning it and trying to rebuild sectors. There are many reasons for this, but the most important one being that the drive can die in the process of running Spinrite. It is possible to do more damage to the drive by doing excessive read and writes. There are times that you only get once good chance at data and if you use a tool that just goes in and surgically removes the data you want BEFORE doing the scan you will be a lot safer.

If I was going to use Spinrite, I would get everything I could off the drive to another destination first and then use Spinrite to try to get anything I could not repair (although I never have to with the tools I use). Another horrific story I have seen with drives sent to me, is that if Spinrite it runs successfully, people are under the impression that the drive is repaired and is usable again and continue to use it. Big mistake and it usually dies again shortly. On a Windows Hard Drive I would try NTFSExplorer/FatExplorer first in the hopes of doing a surgical recovery as oppose to spending days rewriting sectors in the hopes that my drive can live though it as Spinrite does. But for $80 it is well worth the attempt if you are going to do nothing else. Good Luck.

Oct 6, 2008 11:26 PM

Also, you can find some very interesting papers/presentations/videos here.

I am referring to a blog entry from Scott A. Moulton who is a forensic and data recovery expert and currently teaches the SANS 606: Drive and Data Recovery Forensics course.

Spinrite is not data recovery software. I get many questions about why I left off Spinrite on my recommendations of recovery software. I specifically leave off Spinrite because under the strictest terms it is not data recovery software. Almost every single data recovery package knows, and will warn you not to write the data back to the original source drive. Data Recovery/Forensics software almost always recover from a source to a destination. Spinrite does not do that, it refreshes the surface and controls reads to get the maximum amount of data from the sectors and then puts it back down on the same drive.

I think it does quite a few things very well and it does an excellent job at reporting and reading the SMART info and refreshing the surface of the hard drive. However, I would like to first try to get the data from the drive before scanning it and trying to rebuild sectors. There are many reasons for this, but the most important one being that the drive can die in the process of running Spinrite. It is possible to do more damage to the drive by doing excessive read and writes. There are times that you only get once good chance at data and if you use a tool that just goes in and surgically removes the data you want BEFORE doing the scan you will be a lot safer.

If I was going to use Spinrite, I would get everything I could off the drive to another destination first and then use Spinrite to try to get anything I could not repair (although I never have to with the tools I use). Another horrific story I have seen with drives sent to me, is that if Spinrite it runs successfully, people are under the impression that the drive is repaired and is usable again and continue to use it. Big mistake and it usually dies again shortly. On a Windows Hard Drive I would try NTFSExplorer/FatExplorer first in the hopes of doing a surgical recovery as oppose to spending days rewriting sectors in the hopes that my drive can live though it as Spinrite does. But for $80 it is well worth the attempt if you are going to do nothing else. Good Luck.

Oct 6, 2008 11:26 PM

Also, you can find some very interesting papers here.

I am referring to a blog entry from Scott A. Moulton who is a forensic and data recovery expert and currently teaches the SANS 606: Drive and Data Recovery Forensics course.

Spinrite is not data recovery software. I get many questions about why I left off Spinrite on my recommendations of recovery software. I specifically leave off Spinrite because under the strictest terms it is not data recovery software. Almost every single data recovery package knows, and will warn you not to write the data back to the original source drive. Data Recovery/Forensics software almost always recover from a source to a destination. Spinrite does not do that, it refreshes the surface and controls reads to get the maximum amount of data from the sectors and then puts it back down on the same drive.

I think it does quite a few things very well and it does an excellent job at reporting and reading the SMART info and refreshing the surface of the hard drive. However, I would like to first try to get the data from the drive before scanning it and trying to rebuild sectors. There are many reasons for this, but the most important one being that the drive can die in the process of running Spinrite. It is possible to do more damage to the drive by doing excessive read and writes. There are times that you only get once good chance at data and if you use a tool that just goes in and surgically removes the data you want BEFORE doing the scan you will be a lot safer.

If I was going to use Spinrite, I would get everything I could off the drive to another destination first and then use Spinrite to try to get anything I could not repair (although I never have to with the tools I use). Another horrific story I have seen with drives sent to me, is that if Spinrite it runs successfully, people are under the impression that the drive is repaired and is usable again and continue to use it. Big mistake and it usually dies again shortly. On a Windows Hard Drive I would try NTFSExplorer/FatExplorer first in the hopes of doing a surgical recovery as oppose to spending days rewriting sectors in the hopes that my drive can live though it as Spinrite does. But for $80 it is well worth the attempt if you are going to do nothing else. Good Luck.

Oct 6, 2008 11:26 PM

Also, you can find some very interesting papers here.

http://www.myharddrivedied.com/

Unfortunately, the presentation materials are not available at the URL he mentions, but they are available at http://www.myharddrivedied.com/

No, HDD's are hermetically sealed. They have to be.

Actually, no. Look at any consumer drive and you'll see a hole with a sticker besides it with an arrow that says "do no cover this hole". This is to equalize pressure, otherwise the cover would bulge and warp. (There is a filter under the hole so particulate matter can't get in). Yes, there are some very special disks used in the military and NASA and the like that are hermetically sealed mainly to keep moisture from condensing on the platters, but you don't have one of those drives, trust me.

Spacing between head and platter can be in the microns. Turbulence from the rotation of the disk actually aids in making sure the head does not contact the disk.

Yes, and the turbulence (it's actually the boundary layer) that keeps the head off the disk is air, which gets less dense with increasing altitude, and so it gets thinner, ergo crash. What I meant was that perhaps the designers knew this and included a shut-out circuit that detects low pressure and doesn't allow the drive to spin up.

See: http://www.storagereview.com/guide2000/ref/hdd/op/heads/opHeight.html or Scott Moulton's fantastic drive recovery videos: http://www.myharddrivedied.com/presentations.html for more information

One might be humidity, another the decreased frictional constant of the air around you, viscosity of the air is what the internal fans rely on to cool the circuitry and heat producing chips, that the air is thinner means decreased cooling capacity.

Actually humidity drops with altitude. I agree that there is much lower cooling capacity at higher altitude, although it has nothing to do with viscosity or a frictional constant. Air is less dense at high altitudes, so the volumetric heat capacity of air is lower at high altitudes, so for a given volume of air that your fan moves, a lower mass of air is blown over the chip at higher altitudes, and there is less cooling. So sure, it could be a heating thing, no doubt. Whether it be for hard drive protection or thermal reasons, the cut-out would probably be tied to a pressure sensor, since at high altitudes, the thing won't even turn on (it doesn't freeze up like an overclocked computer). Many camcorders, digital cameras, etc. won't either. I have a few solid state gizmos that don't like high altitude either. In any case, the SSD can go higher.

... (and yes, when I said I was a biologist who works in high altitudes I should have said I am a biologist who works on heat balance physiology of high altitude organisms)