How to fix a laptop that reboots randomly - Jan van den Berg

How to fix a laptop that reboots randomly

6 June 2026

My daughter has had a laptop for two years now. For school. But not just for school: the thing is used for everything (i.e. Minecraft). And if she isn't using it herself, the youngest one is sitting on it.

At the end of April, she started complaining: my laptop just shuts down!

I took a quick look: what kind of junk is all this? VPN software and whatnot (long story, another blog). I explained that if you put all sorts of junk on your laptop, it becomes unreliable. I uninstalled a few things and, above all, placed the responsibility on her: this is your laptop, you have to take good care of it.

In the past, you gave children a pet to teach them responsibility; nowadays, it's a laptop.

But the complaints didn't stop; they even seemed to get worse. But she understood: this is my problem. So, no complaining, but finding solutions herself.

Until last week, when she uttered the magic words: “I went to the school’s IT department.”

This was a slap in the face. Aha, so this is what happens when you expect too much responsibility from your children.

The school's IT…. Ugh.

“So, what did he say?”

“That I had to reinstall Windows.”

Now, I’m not the biggest fan of Windows, but this just sounded like an easy answer from someone who didn't feel like it or didn't understand it.

“Well, let's see then.”

First, I decided to install some updates. Firmware too. There were quite a few ready to go.

But after a few reboots, I started having the problem too. I would be doing something and the laptop would shut down?

Uh?

But: sometimes it did, sometimes it didn't. Sometimes immediately, sometimes after a while.

And yet, I could also leave the laptop on all night without anything happening.

[This is the point where I should have or could have known what the problem was]

Windows isn't exactly reliable, but I didn't feel like reinstalling it just yet. But this seemed like an excellent moment to put CachyOS on this laptop. An alternative operating system that will make the laptop fly.

However, during both attempts to install it, the laptop kept shutting down.

This is an important observation.

Because: this means that it is not a software problem, but a hardware problem. After all, installing another operating system bypasses Windows entirely.

Okay, what does HWmonitor say?

I managed to run an analysis with HWmonitor just — before the laptop shut down — and one thing really stood out: the laptop's temperature peaked at 100 degrees.

That is not good.

It was already late. I'll have to take a look with the screwdrivers later.

After the bottom of the laptop was off, the problem was immediately clear after some poking: the fan inlet on the bottom of the laptop was full of dust.

Top left was full of dust

It could be pried out with tweezers.

This can happen when you place a laptop on your bed or on the carpet (which teenage girls tend to do a lot): the fan will suck all sorts of dust inside. That dust then accumulates on the exhaust side. So the fan may be spinning, but it can no longer dissipate the heat. The temperature rises, and then the thermal protection kicks in: the laptop shuts down. Fortunately, otherwise you could burn up your own laptop or, even worse, cause a fire.

When you don't do much with the laptop, it stays on, but if you do something ‘heavier,’ the fan kicks in and that’s when things went wrong. That is why I was able to leave the laptop on all night without rebooting; the laptop wasn't doing much at that moment.

Along with the lint and dust came some plastic and snapped-off parts: teenage laptops have a tough life. But, put in a few new screws, and the laptop is running like a dream again.

Daughter happy, father happy.

History repeats itself

Why could I have known this?

I had exactly this problem back on May 27, 2006. So, almost exactly 20 years ago, because this happened last week.

This was with the most worthless laptop I have ever owned, a Packard Bell with an AMD XP-MC PU. I understand that you have to own AMD shares these days, but ever since that laptop, AMD has been suspect to me. I prefer not to have AMD, and that is because of that laptop.

Anyway: the design of this laptop wasn't very great, which meant it collected and sucked in a lot of dust. And when I ran jAlbum (heavy CPU usage), the laptop would shut down. I had made a post about this on the jAlbum forum — because I thought it was jAlbum's fault…… — but with more ore less the same photo as the one above.

Dust was the problem there too. That forum, or that post, no longer exists: I retrieved the date from my email archive, which is why I still remember this date. And I still have the photo I used with the post:

It is now exactly 20 years later, and this is still a problem for laptops.

Although, it is actually nice to know that I am typing this from a Macbook M4, you know, a fanless device.<br>Tech

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