Do computer system units actually go up in flames?

There's a strong belief amoung non-technical people that home computers should not ever be left on unattended - since they are electrical devices and can go up in flames and set the room on fire.

Now it's obvious that any component inside the computer system unit can break at any moment and maybe even produce a fair share of toxic smoke. But do computers actually go up in flames that can cause a fire around them?

Solution 1:

I think we should distinguish between 'conflagrations' which emit a little smoke, and overheating which might cause fires by contact with something flammable.

Reputable computer hardware manufacturers use components which do not accelerate fires and are flame-retardant so far as possible.

The Underwriters Laboratories rating system requires these things, but Gnoupi is right about power supplies: don't buy very cheap "noname" power supplies: they may have been designed with no regard for safety considerations.

But, by and large, computer system unit don't go up in flames ... although there may be a few exceptional 'cases'.

Solution 2:

Seems that yes, according to this answer (and some others on the same question).

In general, the parts that can actually catch on fire are batteries. It's a problem which concerns laptop, but only in some faulty cases. Check this article for more information.

For desktop computers, if there is a cause, it's the power supply. Buying very cheap "noname" power supplies is actually dangerous, because many are faulty, and not handling the power ranges they claim. Not sure if that would be enough to start a fire, but clearly enough to make sparks and shut down power in your room/house. It's a French link, but you can check the video on this page, where the tester is checking capability of some noname PSU (direct link to video).

Solution 3:

My wife had a hard disk drive catch fire on her once, back in the old PC days. The computer was in a sporting goods store, very close to the skate sharpener, and she could taste the metal in the air when she used it. Since then, no problems.

However, thousands of companies leave thousands of computers on 24/7 without problems, so for a computer in known good shape in a known good environment, I wouldn't worry about it.

Solution 4:

A modern PC? It's highly unlikely - your motherboard has temperature sensors, and will cut out if they get too high. If voltages suddenly start going off the chart, your motherboard will cut power. Your motherboard catches fire? Well, there's not much it can do about that, so it's still possible - just unlikely.