I have a Seagate Momentus 5400.6 500GB laptop drive (ST950032 5AS) in an iomega external USB enclosure which a friend has given me to look at.

With the drive in the enclosure, when I plug the unit in it spins up OK, I hear what sounds like a little head activity initially, it doesn't make any unusual noises such as clicking, the USB connects but only shows as simply "Storage" in Devices and Printers (Windows 10).

It shows as "ST950032 5AS" USB Device in Windows Device Manager, but the Disk Management section of Computer Management initially hangs when it's connected, and then comes up with a message saying the disk needs to be initialized, but when attempting to do so, fails with an I/O error. There's no audible disk activity at all during this time.

If I take the disk from the enclosure and put it in my external caddy (ICY Dock) it's not recognised at all.

If I put it in a laptop in place of the original drive, it's recognised by the BIOS, but won't boot from it. I've tried booting SpinRite from a USB but it also hangs while trying to identify the drive.

So any ideas a to what it might be? Would a PCB swap be worth attempting, or is it more likely to be mechanical in nature?

Neither PCB nor mechanical, judging by what you've stated.

Almost certainly media issues.

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