If your hard drive doesn't rev up anymore, it could possibly due to bearing damage. In this case the only thing that helps is the professional change of the bearing during a data rescue..
Attingo has more than 22 years of experience, professional competence and know-how, special technology and tools in order to temporary recondition hard drives with bearing damages.
Amongst other things:
The spindle ball bearing deadlocked, the discs cannot move or rotate anymore
Older hard drive models - especially SCSI hard drives - have a ball bearing, new models have liquid bearings, which are significantly more quiet and run with fewer vibrations. The discs are positioned on a wave, called spindle, assembled one above the other. Dependent on the capacity and type of the hard drive the number of discs and write/read heads varies. Readjustement of the discs and data recovery are therefore very laborious.
The write/read heads are floating just a few nanometer over the sensitive magnetic discs on an air cushion. For comparision: fine dust particles have a size of 10 micrometers, which is a few times bigger than the fine air cushion inside the hard drive. The tiniest imbalances may cause the write/read heads to impact on the data carrier surface. In succession the magnetic layer gets damaged fatally. A data rescue is often no longer possible after that.