Hard drive model: Seagate ST3500413AS 500GB

Customer reported symptoms: Not detected in BIOS, can hear clicking sound when powering on the drive
Data Requested: all work documents (Word, Excel, PDF and Outlook pst backup files)

Initial assessment with our specialized device have been performed, and determined that heads are damaged. When we opened the chassis in our clean rooms, it was immediately evidence that the heads had failed as a result of the impact. Apart from some media damage, thankfully the platters were otherwise fine.
The internal moving parts of a hard drive are very sensitive, the slightest jolt or drop can result in the liquid bearing seizing or more commonly the read/write heads suffer physical damage. Hard drives that experience more severe shocks from being dropped from 2 to 4 feet onto a very hard surface can not only damage the bearing and or heads but also the platters can actually shift off center.

The unique pre-amp information on the heads, meant that we had to find identical parts as donors. The head swap procedure is pretty straight forward on these drives, and it was completed successfully. However, when we started the imaging process the drive would only read a few sectors at a time, and then reset, read a few more sectors and reset. We then tried to reverse image the drive, but had the same results. We then skipped forward from the beginning to about the 10 millionth sector and started imaging from there. We were able to get a clean image for the remainder of the drive, and when it cycled back around to pick up what was skipped at the beginning, it was also able to read this without any problem.

Occasionally we see these kinds of problems with drive imaging, where it seems impossible to image the drive at first, but then it "magically" starts to perform perfectly. This is most likely caused by some minor particle contamination on one of the heads which is cleared up as the drive continues to operate. In cases where it doesn't clear up, then we will take those heads and attempt to clean them, and if it is still not working properly, we will try a different set of heads, since it may be an alignment issue.

Result: every single file has been recovered, without any corruption. The client was very grateful.
Cost: $300

Turnaround: 4 days