Four drives came across my bench last week. Every one of them held the only copy of something.

None of them died quietly. Every one gave a warning first, and in most cases the warning had been going for weeks before anybody called me.

Here is what to listen for.

Noises.

A spinning hard drive has a motor and an arm inside it. When those go wrong, you hear it. A soft click every few seconds. A tick that repeats. A grinding or scraping. A drive that spins up, stops, and spins up again in a loop.

Clicking is the one that matters most. If a drive is clicking, turn the computer off. Do not restart it to see if it does it again. Every power cycle after that spends some of what is left.

Quiet is not necessarily proof of health. SSDs have no moving parts, so they never make a sound no matter how bad things get.

Slowness that comes and goes.

A file takes thirty seconds to open and then opens instantly the next time. The computer freezes for a few seconds and comes back. A copy runs fine for a while and then crawls.

That pattern is a drive rereading a spot it cannot read cleanly. It tries again, and again, and eventually gets it. That is why it comes back. It is also why it gets worse.

Files that open wrong.

A photo opens half grey. A document opens as symbols. A file that was fine last month will not open at all. Programs that used to launch now throw an error about a missing file.

The message from Windows.

Sometimes you get told outright. "Windows detected a hard disk problem." "SMART failure predicted." SMART is the drive reporting on itself, and it counts its own errors. When it says a failure is predicted, it is telling you it has already been struggling for a while.

People click past that message for weeks. I have seen it dismissed daily for a month.

SSDs are different.

An SSD gives less notice and goes faster. The common ending is that it flips itself to read only, so you can open everything and save nothing. Or it is there one morning and gone the next. There is rarely a long decline.

There is one more thing about SSDs worth knowing now rather than later. When you delete a file from an SSD, it does not sit there recoverable the way it does on a spinning drive. The drive clears it out on its own in the background. Deleted files on an SSD are often gone in a way that no software gets back.

What the warning is worth.

A failing drive is still a readable drive, right up until it is not. That gap is where everything good happens. Copying your files off a drive that still works is quick and cheap. Getting them off a drive that has stopped is neither.

So the window is the point. It is usually days or weeks. It is never as long as you think it is when you are in the middle of it.

If your machine has been doing any of this, stop using it for anything that matters and bring it in. I can tell you inside ten minutes whether the drive is dying, and if it is, I can copy it while it still reads.

Tomorrow: the times Windows says the drive is gone and the drive is fine.