Is Your Computer a Fire Hazard Waiting to Happen?

whoppers asks: "I'm sure we've all had our share of computer fans die, but what happens if your box is running while you're at work and several fans go out? My in-laws spare TigerPC AMD K62-400's power supply fan just went out about two hours ago, and the thing was blazing hot. A little poke to the blade, and it started up again, but shouldn't these things be made to stop if the fan stops for any reason? I'm starting to wonder if I should start leaving my box off when I'm away for a few hours. Since it's usually wide open, I don't see too much harm, but these cheap boxes that never get opened and cleaned have to be a hazard right? I can't afford a halon system in my office just yet. The only link I found related to this is here and should a few more people read this, here's the cached version. Does anyone have any thoughts or stories related to this?" The fact that this article appears on July 4th, when most Americans will be lighting fireworks is purely coincidental. That doesn't change the fact that the submittor raises a very good point. A general rule of computers is: the older they get, the more dusty they are and dust bunnies and their denser cousins are highly flammable. Unless you can keep such machines clean, it' is probably safer to leave them off.

Keep your system clean!

[ReverendRyan]

IF you dont let the dust build up by useing a vacuum onece a month or so, that drasticaly reduces the fire hazard. Of course, that doesnt mean your CPU fan wont fail, causing your CPU to burn right through your motherboard if you dont have overheat protection. ;-)

monitor fire hazard

[eagl]

At work they made a policy that ALL computers will be completely shut down at night after a monitor caught fire one night and burned out an office. Normal hardware shouldn't catch fire even when old/crusty but there's NO guarantees when the hardware is defective to start with.

Dust filters

[scott1853]

How come nobody has made a case with an air filter on it so you only have to brush off the filter every month instead of taking a can of air to the box?

Poll

[Kingpin]

Instead of chasing windmills, let's have a poll on this.

Spontaneous computer combustion:

( ) Seen it
( ) Heard of it
( ) Heard of someone who heard of someone who...
( ) Nope

My point is, is this really an issue to worry about?

Re:If your power supply is UL/CSA approved

[tzanger]

Destroy itself? Hopefully it wouldn't destroy itself in a firey ball of flame...

that is one of the things that UL certified equipment is tested for, numbnuts.

Basically they put cotton "fleece" around all the openings and cause a catastrophic fault. If any of the cotton burns, you fail.

With our power electronics equipment, the fault consisted of shorting out the load side of our equipment while we were connected to a bus capable of delivering 100kA. We passed just fine, but it was the fuses which afforded us that protection. Remove the fuses and the results are ... well... spectacular.

Re:KAAABOOOOOM!!!!

[Anonymous Coward]

Thankfully it would be very hard for a screen to explode. I can't imagine any failure mode except manufacturing defect in the glass itself. The glass on a montor is quite thick and strong so as to withstand the high internal vacuum. If anything, a screen would have a natural tendancy to implode because of the negative internal pressure.

Re:Fire insurance discounts?

[Sircus]

Maybe insurance companies should offer discounts to those of us with common sense enough to buy and configure motherboards that have a "Power Off on High Temperature" option in the BIOS.

The fact that they don't is probably sufficient indicator that the incidence of overheating motherboards burning people's houses down is very low indeed.

fan speed sensing

[frovingslosh]

Many, if not all, newer motherboards have temperature sensing (a must for the Athlon chip). Some even have extra inputs available if you want to add extra temperature sensors.

Perhaps more applicable in this case is that these boards also offer inputs for fan speed sensing when used with an appropriate fan (generally the ones with 3 wires and a small tach sensor built in). Unfortunately, I have yet to see a power supply that comes with such a fan and provides the sensor feedback to go back to the motherboard. (I'm not saying they don't make them, just in my limited experience I haven't seen any.) If you could find the right size fan with the speed sensor you should be able to install it in the power supply and route it to the MB though. If there was enough demand voiced I expect the sensor would start showing up, but manufacturers would have to know that some people we basing case purchases on this feature.

This doesn't help older systems like this Tiger system much, but the issue has been addressed. There also have been available for quite some time temperature sensors that you installed in the case and they would sound an alarm when a critical temperature was reached. Several years ago I had a programmer build some watchdog timers for some critical systems with PIC chips and we decided to add a Dallas temperature sensor. By tapping on the reset button a few times you could get it to beep the internal case temperature back to you.(Obviously, you didn't reset the computer - the watchdog took over the MB reset input so it could reboot the system if it detected a failure. A long press of the reset could still reset the system through the PIC chip.)

This is reasonably timely for me, just yesterday I started getting alarms that my CPU fan was erratically slowing down. So far CPU temp looks good, but I'm going to have to replace the fan (if I can find an available fan of the right size with a speed sensor) or the whole heat sink assembly. I do have another 12 volt fan with the right hole pattern, but it lacks the speed sensor and is much thicker. Maybe I could find some really long metal screws and stack both fans above the heat sink, count on the new one to cool the CPU, but the old one to help and to continue to monitor the RPM and airflow. Any thoughts?

P4 does it well

[txgaia]

Toms Hardware did a test where the heat sink was removed from 4 kinds of processors while they where in heavy use. The P4 stepped down the speed until it managed a safe temp. The P3 halted and the two types of Athlons incinerated. (It hit 698 degrees almost instantly once the heat sink was removed.) Maybe the P4 is worth the extra cash. http://www.tomshardware.com/cpu/01q3/010917/index. html

Re:Cheers, slashdot

[MonMotha]

VaxWars [remote.org] has an insteresting story about that very thing. Rather humerous read. After you read that, I reccomend you check out the VaxBar [arizona.edu] for another good laugh.

--MonMotha