[SOLVED] Data Recovery: Hard drive not detected, spins, but not to 7200 rpm: Prognosis?

Mrcreosote

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Feb 18, 2016
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A 1TB HDD from a Dell XPS 430 became undetected even in the boot BIOS.

Checked on another PC, is not detected and it spins up, but clearly to an rpm <7200.

Wondering what most likely failure might be and data recovery cost. (and where to send for DR.)
 
Solution
I doubt very much that the drive isn't reaching its intended speed. The most likely reason for non-detection is that the drive is performing internal error recovery functions which are causing it to remain busy.

These modern drives use a 3-phase brushless motor with no Hall effect sensing. Instead the motor controller drives each pair of phases in sequence, while the back EMF in the third phase is used to sense the speed. The heads remain parked on the ramp during this time, so the read head is not reading the servo information.

For more info, read the datasheet for the L7250 SMOOTH motor controller:

http://pdf.datasheetcatalog.com/datasheet/SGSThomsonMicroelectronics/mXyuswx.pdf

Some drives, eg Seagate and Samsung, have a...
D

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You should just use a search engine for find a data recovery places that are close to you and what the costs are.

As to the reason of why it fails, who cares things get old and break. At the end of the day, it doesn’t matter. the fact is that it’s undetectable it doesn’t work on any system. so you just have to accept that it’s broken. and why would you even care what it was that broke? You’re never going to find out and nobody here is going to be able to tell you

Most likely the electronic board has failed
 
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Mrcreosote

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Feb 18, 2016
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Thanks for sharing your opinion about it being the board.

I can do the repair. I have all the stereo microscopes and soldering gear to do SMD. I do micro trace repair on mobos. I just haven't gotten into HDD's other than extracting the magnets.

I suspect the board also. Possibly if really lucky, the contacts given so old.

I could remove the board and give it a good look and maybe I'll find something. Check all the diodes.

I'd like to know more about the motor drive circuitry.

I could find a replacement board and transfer the firmware.

However I'm concerned it could be the motor but I also think that is unlikely.
 
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and why would you even care what it was that broke?
Well - we could dig in if possible.

Here is some possible reasons why the spindle motor doesn't get into full speed:
  • Write head or platter is so damaged that it cannot retreive anything, so it cannot regulate the speed (if that is the way of rpm feedback) for the spindle motor controller.
  • Rare electrical damage to spindle motor itself or driver circuit.
    • If let say there is a connector to the spindle motor that is faulty, then the driver circuit simply cannot feed it with full power.
If it turns out being a bad connection between the PCB on the harddrive and the pins that leads to the spindle motor (i.e. rare case of grave corrosion), there is a slight chance that use electrical spray (CRC something I think those spray boxes are called if I remember correct) just may make the hdd live some few moment longer. However that is a long stretch and the fault can be anything else.
 
I doubt very much that the drive isn't reaching its intended speed. The most likely reason for non-detection is that the drive is performing internal error recovery functions which are causing it to remain busy.

These modern drives use a 3-phase brushless motor with no Hall effect sensing. Instead the motor controller drives each pair of phases in sequence, while the back EMF in the third phase is used to sense the speed. The heads remain parked on the ramp during this time, so the read head is not reading the servo information.

For more info, read the datasheet for the L7250 SMOOTH motor controller:

http://pdf.datasheetcatalog.com/datasheet/SGSThomsonMicroelectronics/mXyuswx.pdf

Some drives, eg Seagate and Samsung, have a UART interface that reports diagnostic information during spin up. A cheap USB-TTL adapter will enable you to see these error reports.
 
Solution