Dead HDD

[#1]

After swapping a couple of HDDs around and removing two old PATA drives one of the remaining SATA's failed to be recognised, even in BIOS. After swapping both data and power cables from a known working drive it seems that it is as dead as a dodo. No vibration at all and even tried it in an external caddy.
The things is, when it is placed in the caddy the PC beeps as it recognises that a device has been added but still no power getting through to the drive.
It's a 1TB drive about 3/2 full which SWMBO never backed up and it it MY fault
Baring in mind the above what can be done, if anything, to recover the data. The drive is still under warranty but don't want to send it off until we try a recovery.

[#2]

On modern HDD, it is more often the electronic circuit board that fails - rather than the actual spinning disks or flying heads.
You should be able to get a replacement circuit board relatively cheaply, and then it should just be a matter a few re-soldered connections to get it running again.
The fact that your motherboard BIOS can't see the drive correctly would tend to indicate that your HDD has a PCB fault.

[#3]

You will need a replacement board for the exact same model of drive.
I think the actual desoldering and soldering will require some very fine work.
Here is a laptop drive example - a 31/2" would be slightly larger scale.

[#4]

You should only need to disconnect the flexible printed circuit lead between the PCB and the drive mechanism, which should only be about 5 or 6 connections.
Depending on the drive, these printed circuit leads often have a push fit connector - so you might not have any soldering to do at all.

[#5]

This wouldn't be a Seagate 7200.11 drive by any chance....
If so, you may have faulty firmware which causes a permanent BSY error, the symptoms of which are those you describe.
I've just unbricked a 500Gb model with the help of these guys...
http://www.msfn.org/board/topic/128807-the-solution-for-seagate-720011-hdds/
cheers
Graham

[#6]

That's some heavy reading 😮
It's a Samsung. I understand that Samsung were bought out by Seagate but it is still Samsung labelled and no mention of 7200.11 anyway. But thanks for the info.

[#7]

Yep, I thought that too 
Took several hours to work out what I needed to do, and spent a very careful 3-5 minutes unbricking and it was all done. Saved me the expense of a new drive, but I do have a rigorous backup routine in place now for the important stuff.
Trouble is, Seagate don't recognise it as their problem and wanted to charge the normal going rates for data recovery. An expensive job from my point of view, but a nice money earner for them.