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It appears that freezing your hard drive (literally placing it in a freezer for 12-24 hours) might help to bring the drive back to a temporarily working condition. Google has many links to various blogs where this issue is brought up and the concept proven to be working for some people.
What happens to the drive when it's being frozen for that amount of time on a mechanical level and why does it work?
XXL
Posted 2011-11-04T11:50:52.377
Reputation: 1 359
5
I cannot cite source but in some IBM training a number of years ago, the instructor mentioned that there was also an effect of the metal parts moving as they became cold. A platter then might be in a slightly different position and be readable. The cold might also free a stuck spindle as the spindle and bearing contract differently. It may also change the position of the heads on the platter.
Dave M
Posted 2011-11-04T11:50:52.377
Reputation: 12 811
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Cold can have an effect on magnetism, because cold can have an effect of how fast charged particles move. It is the motion of charged particles, usually electrons around a nucleus, that produces magnetic fields. Cooling a metal can make the motion within less random, thus allowing more atoms to line up with each other. This increases the magnetic field of the material. On the other hand, making a magnet very hot will cause more random motion, resulting in less allignment of molecules and less megnetism.
This means colling the HD can restore some particles to the right state so the header will have less problems reading the data of that sector.
m0skit0
Posted 2011-11-04T11:50:52.377
Reputation: 1 317
I've spoken to people who've run drives when actually sat in a freezer when recovering data - never quite gone to that extreme myself, but i'm sure data-recovery companies have a similar enviroment. – HaydnWVN – 2011-11-04T12:31:22.070
I've freezed 3 drives and it didn't help either one. Guess I was just really unlucky. Freezing my 4th drive now. – XXL – 2011-11-04T12:33:51.060
Well this doesn't mean that by freezing you will be able to recover your data no matter what. Depends on what the problem is. – m0skit0 – 2011-11-04T12:35:45.687
Yes, ofcourse. However, each of these 3 drives had a different problem. One with bad sectors, one not spinning up, one not detected in BIOS.. Unfortunately, I was unlucky. – XXL – 2011-11-04T13:08:59.567
Bad sectors could be physically damaged, thus cold won't yield any result. Not spinning is most likely due to a mechanical (engine) problem, and cold won't help either. Not detected in BIOS has probably to do with HD firmware/controller, thus cold is no help either. Good luck anyway :) – m0skit0 – 2011-11-04T13:11:19.667
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@m0skit0: look here -> http://www.datarecoverypros.com/hard-drive-recovery-freeze.html, citing "If the drive is spinning (you will hear it turning) this is not the method to use, this method is best suited for data recovery cases where the drive is not spinning". Judging by Dave's comment below - that's pretty much a situation where cold could help. But ofcourse, it all depends on the angle of the problem, but I'm referring to "most" of the cases. If you read Google results, people say that cooling the drive this way actually made it being detected in BIOS, once again.
– XXL – 2011-11-04T13:22:52.5771But I'm pretty much under the same rational impression as you on the whole matter - just that people seem to be having opposite results for some reason :P – XXL – 2011-11-04T13:29:36.717
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My understanding is that it was a matter of differential thermal expansion. The cold drive will have things in a slightly different position relative to each other than the warm drive. This is especially useful if the fault was a stuck bearing keeping it from spinning up, although I have heard this is no longer normally an issue. I've never actually had a case to try it.
Loren Pechtel
Posted 2011-11-04T11:50:52.377
Reputation: 2 234
It's the 2nd one I've heard: the bearing shrinks faster/more than the platter, meaning the disk turns easier. – Joel Coehoorn – 2011-11-04T13:48:07.670