Helping people with computers... one answer at a time.

Some laptops don't have the proper ventilation to handle a high CPU load for a length of time, which causes them to protectively shut down or crash.

I gave my wife a Nokia netbook running the starter Windows 7 about 2 1/2 years ago. It's increasingly freezing up. It used to be once in a while, but now it's doing it after five minutes or so of operation. It does not seem to make a difference if it's running on the battery or AC. However, it does get very hot. I took the battery and ran it only on the AC and it is still very hot. Any ideas? By the way, all she does via Wi-Fi is surf the net and looks at email and Facebook. We don't know how to use Twitter (if you can believe that).

In this excerpt from Answercast #57, I look at a case where it appears that a CPU load on a computer is causing it to overheat and crash.

Hot computer

Oh, I can believe it. You're not alone in not necessarily paying attention to Twitter.

My suspicion is that your computer is overheating. The fact that you say that it's getting hot... many computers are such that if they get too hot for too long, they'll actually shut down. They'll either crash or the motherboard will proactively and preventively shut the computer down to prevent it from damaging itself further.

Why is it overheating?

Now, the question is, of course, why is it overheating? What I'm going to suggest you do is fire up Process Explorer. I have an article called, "Who's hogging all the CPU?" and I'm going to point you at that:

  • You'll download Process Explorer;

  • You'll run it in a way that will highlight which programs are using all of your CPU.

Probably a software issue

If it turns out that the System Idle Process is using most of your CPU, then I'm wrong; it's not a software issue... it's not something going on with software that's causing too much to be run on your machine.

On the other hand, it is very possible that you may see a program or two consistently at the top of the list trying to use all available CPU for some reason or another.

That would potentially cause your computer to overheat.

Normally, computers are more than happy to do that for awhile. But typically in a situation like this, I have seen software (either malware or software that just has bugs in it) that causes it to use all of the CPU constantly, continuously.

Some laptops don't have the proper ventilation to handle it for that length of time, and they crash.

So, take a look at Process Explorer. See what bubbles up to the top of the list. That's the program you'd then start looking into. It is very possible that that program (at the top of the list) is what is fundamentally at the root of this problem.

Surfing the net

Now, I say that with the assumption that if all you're doing is surfing the net and looking at email and Facebook, in reality, those shouldn't use a lot of CPU. I mean there might be spikes as certain things get drawn on the screen and so forth, but what you've described is fundamentally things that just don't require a lot of horsepower and a lot of CPU time to accomplish.

So, if there is something that's using up all of your CPU, it's probably not intentional. It's certainly not required to do what you're doing and it is something that is basically the next step in your investigation.

Article C5863 - September 29, 2012 « »

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Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

Al Simons
September 29, 2012 12:09 PM

Another possibility is that the cooling system is clogged with lint. One sign of this would be if the fan is running at high speed a lot of the time, yet the computer still remains hot.

The only solution for this is to open up the system and clean it. For laptops this takes some specialized tools and a fair amount of skill. If you think this may be the problem, it may be worth taking your system in for service.

September 30, 2012 12:19 PM

I don't think the problem is the heat now, as it seems to lock up when Internet Explorer is Activited. I wanted to down load the program suggested however, I can't as the computer locks up. I went into Task Master and found the IE is taking a lot of the 1 GB of memory. When I moved the cursor in the Task Master the lock up happens. It also happens when I try to use IE as I stated. So, While heat is there it appears to be something else. This computer was one I bought from Best Buy with connection to the internet built in via AT&T. I removed all of that as I had a MiFi from Comcast (until they discontuned that) and it worked but still locked up now and then. Its now locked up again and I have not tried to get on the internet but Task Master did show IE was taking a lot of memory. I am dead in the water, well my wife is until this is fixed or a get her a new "Surface" from Microsoft.

Ginger Miller
October 2, 2012 10:10 AM

Laptop vents are often on the bottom of the machine and depending upon the surface where it's sitting, it may not be getting enough ventilation. I purchased a rectangular roasting rack at the grocery store and I always put it under my laptop. That leaves about an inch of airspace and solves the heating problems I was having.

October 2, 2012 10:20 AM

I have a slow system with low memory - and when I access multiple sites with lots of pictures, my system gets very very slow - since it is swapping virtual memory. The system isn't hanging, but you can't tell the difference between a hung IE session or a very very slow one. So my question is - do you have lots of sites open? That can really bog you down. This might not help, but when is the last time you deleted temporary files and such in your web browser? If you think it is your browser causing problems, you might want to try that.

Alex Dow
October 2, 2012 11:36 AM

Whilst agreeing with the fore-going comments, I would also ask if you have done any conventional "house-keeping" on the laptop?

Defragging, Chklinks, Ccleaner etc should be run occasionally on your laptop, otherwise it is forced to wotk progressively harder to achieve the same results - looking for thousands of fragments of files, scattered all over the Hard Disk Drive etc.

More technical, if you do manage to open up the laptop, renew any heat-transfer grease/compound, as well as cleaning any heat fins.

Compressed-air canisters and long-haired artist or make-up brushes can be very useful; "but mak shair th're clean afore ye dae it"!

On the physics side, it is reckoned that all energy ends up as heat.

October 2, 2012 11:17 PM

I lean towards blocked cooling vents (more below), but software can be a contributor. I removed Skype for this reason, and have limited the CPU cycles of programs like Seti@Home. Process Explorer can help identify possible culprits, but sometimes its just too many bits and pieces of neat stuff, and you'll have to decide which you really need to have installed and running continuously.

However if heat is the problem the cooling system has to be investigated. For laptops, always use a "cool pad" (or baking rack - very creative!), and never leave a laptop running on a soft surface like a couch or bed for extended periods.

Most laptops have two cooling fans that draw air in and channel it to hotspots (such as the CPU) on the motherboard. If you hear the fans running continuously, or kicking into high gear frequently, there is probably a blockage. Often you can clear the vents without having to open up the case by using the crevice attachment of a regular vacuum cleaner (blowing with a can of compressed air may only drive the dirt further inside). Do this with the computer off - you should hear the fan spin up as the airflow increases. If you don't, you may have a failed cooling fan, replacable under warranty. I do this frequently, especially since I often use my laptop on the patio during oak pollen season.

Desktops, towers and servers also have cooling fans. While the vents are larger and less likely to become completely blocked you'd be amazed what gets in there. I vacuum out the cooling vents, drive and power supply bays of my server every three months, and crack the case on my towers once a year. An accumulation of dust can interfere with the dissipation of heat even if it doesn't block a vent.

October 3, 2012 4:23 AM

I agree with previous comments suggesting that the cooling vents are blocked. a processor will shut down to protect itself from over heating. I've seen exactly this behaviour in my wife's Compaq Presario CQ61 laptop. She's purchased a small stand with USB powered fans to keep the unit cool. I suggest that cleaning the inside of the case would be the best option, but I suspect this would be a specialist job, seeing as we're talking about a netbook computer. I'd happily clean the built up dust from a PC, but I'd hesitate at removing the casing of a netbook. Good luck.

October 4, 2012 1:05 PM

I remember having this issue with my first laptop, and a geeky friend said simply "they should never have called these computers laptops, using them on your lap will cause overheating". I followed his advice and always use my laptop on a riser balanced on my lap ... problem solved. Gotta love the "roasting rack" idea though, I'll be checking them out when my Fellowes riser bites the dust.

October 13, 2012 3:51 PM

I have to agree with Al Simons, Although they are called Laptops i think the worst thing one can do is put them on your lap! Unless you have some kind of lap table. Even worse is when kids use them laying down on the carpet.

December 9, 2012 12:00 AM

So far my laptop has had overheating problems from three different sources:
1. It had dirt and sand on the inside. After a good cleaning by a technician the problem went away.
2. A slip of paper got under the laptop right where the fan intake is. No air means quick overheating. Solution: scold yourself and remove the paper.
The third one is still with me: occasionally Adobe Flash Player 11 starts to race, using about 30 percent of processing power. Using Process Explorer this problem is easy to identify and a quick restart of the Player will resolve this problem.
A tiny program, CPU Thermometer will keep track of the internal temperature of your laptop. Start to get concerned if the temperature gets in the 70C neighborhood. Google it, download and install the program.

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