The most common cause and a plan of attack.
By “crash”, we mean things like random blue screens, black screens, reboots, freezing up, or shutting down, all without warning.
I find one cause to be the most common by far.
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The most common cause of random crashes is an overheating computer caused by blocked airflow or a failing fan. Pay attention to how hard your computer is working at the time of a crash — high usage can exacerbate heat problems. Other causes include hardware failure of RAM or disks, and — much less commonly — malware.
Heat is the enemy
The most common cause of random crashes is an overheating computer.
The most common cause of an overheating computer is blocked airflow.
The most common cause of blocked airflow is an accumulation of dust and debris.
Fans in your computer blow air through its components to cool them down. Your computer’s CPU, hard disk, and other components all generate heat — sometimes a lot of it. If the components become too hot, they can fail and cause a crash.
Particularly in laptops, it’s easy to accidentally block the air vents allowing air to flow through the device. I recommend not putting a laptop on your lap — use a table or “laptop desk” to ensure proper airflow.
Desktop computers are more vulnerable to dust and pet hair, which can clog the vents. It’s worth unplugging your computer and looking inside. Carefully clean it if you find a lot of dust and dirt.
After blocked air vents and dirt, the next most common cause of an overheating computer is a failed fan. Fans have become complex over the years. To reduce noise, computer fans often operate at variable speeds, running quietly at a slow speed when things are relatively cool and speeding up to move more air as the computer heats up.
Heat and your CPU
The temperature inside your computer can change depending on what you’re doing.
The harder the computer’s CPU works, the more heat it generates. That’s why variable-speed fans make sense — if your computer is idling, you don’t need the fans to run at full speed. On the other hand, if the CPU is working hard, the fans speed up to cool things down as the internal temperature rises.
Listen to or watch your computer’s fans as you use your computer. If they never turn on, there’s almost certainly a problem with the fan or its control circuitry.
Your computer should be designed to handle the maximum heat its CPU can generate. Even if your CPU is at 100% usage, the fans should keep up. A machine crashing randomly the longer it is used or the harder its CPU is put to work is a warning that there’s an overheating problem.
Check for overheating first.
After that, it gets more difficult.
Other causes
Malware is no longer a common cause of random crashes. These days, malware is more interested in keeping your machine running so it can do its malicious work. Certainly look for malware, but don’t be surprised if you don’t find any.
Failure is always an option. Hardware can fail. We think of hardware failure as being instant, total, and catastrophic, but various components can have intermittent, delayed, or random types of failure.
Next to the fan, failing RAM is the most common hardware-related cause of random crashes. Programs don’t always get loaded into the exact same place in memory, which means you might sometimes access bad RAM, causing a crash immediately or afterward.
Software is what people think of first, but the vast majority of software errors do not cause your computer to crash. More commonly, a program may crash or terminate unexpectedly, but Windows itself will keep running.
The exception is device drivers. A bug or other unexpected error in a driver could cause it to fail and crash the entire system. If you’ve recently added hardware involving new or additional drivers, or if a recent update included drivers, then it belongs on your list of suspects.
The hard disk (either HDD or SSD) deserves special mention. A disk with bad or damaged information affecting any of the software — including Windows itself, drivers, or your applications — might cause a crash. You’ll usually get warning signs, such as significant disk slowdowns or even “bad sector” or “CRC” errors before the crash.
Do this
Here’s a plan of attack for a computer crashing randomly.
- Make sure it has unrestricted airflow.
- Make sure it’s free of dirt and dust and that the fans are working properly.
- Run a CPU temperature monitoring tool. Speccy is a free tool that displays this and more.
- Run a memory diagnostic such as Memtest86.
- Run a hard disk diagnostic as provided by your disk manufacturer, or run CHKDSK /R.
- Make sure the operating system and device drivers are as up-to-date as possible.
- Make sure your security software is running and up-to-date.
And as always, if the crashing started after a recent change, consider reverting to a system backup taken prior to the change.
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I have a Blackbird 002 from 2007 rebuilt in 2010 that has windows 7. It was crashing and rebooting and diving me crazy for a long time. I finally took a guess at the problem and turned out to be correct. I disconnected everything, opened it up, pulled out the 24 GB of RAM, and reseated the 6 RAM cards and the problem has been gone for a year now. I seemed to have remembered this fixing the same problem in this or another desktop years ago. ust simply reseating parts that plug in
One thing you can do to mitigate the effects of a computer crash is to save your work often. In most programs this is the CTRL+S keystroke combination. It won’t stop your computer from crashing, but it will prevent data loss in case of a crash. Press CTRL+S often. Many programs such as MS Office do automatic saves every so often. I’ve set the default interval between saves to one minute. Computers are so fast these days that it’s totally transparent. I still do periodic CTRL+S saves as the automatically saved document isn’t always as easy to recovery as your personally saved file.
When entering data on a web page, I often type CTRL+A to select the text in the data entry fiels and CTRL+C to copy it to the clipboard. If anything happens to the program I’m typing in, I just paste it back, and if the computer crashes, I can get the data from my clipboard manager. I use the free Ditto program.
I gotta say, there are times when I use Google Chrome to fill in data on a webform and my “time limit” to submit the form expires. CTL-A, CTL-C vitally helpful in that case.
As always, when I encounter a “crashing” pc, I open it up and grab my trusty can of aerosol duster and clean out the machine. In 95% of the cases, this fixes it. When I see clouds of dust, I smile cause that is the issue. People are afraid to open their pc and this is a big mistake. It is only a cover and nothing more. Clean your machine regularly anyway, Especially if it is in an area of poor housekeeping.
I have to put in a plug for speedfan 4.52. Marvelous freebie monitors many sensors including CPU temperatures and fan speeds in your computer and will even give a report on S.M.A.R.T. attributes of your HDDs, along with a link to a website that will give detailed HDD info.
Remember, passive monitoring is no substitute for actively cleaning the dust from your computer’s innards.
That last warning is true, but a temperature monitor can warn you that you need to do a dusting. 🙂
If you choose to build a computer it is possible to kill two birds with one stone so to speak what I suggest to build a computer of your choice in the ASETEK Vapochil Lightspeed XE-II PC case it might not look very attractive but it will keep the CPU at a nice frosty -70 degrees below zero provided you followed the CPU install instructions and coated the areas you don’t want to get wet with liquid rubber and allow it to cure before installing in said case
my dell desk top computer doesn`t crash, it keeps switching
from normal mode to safe mode on different start ups. i`ve tried msconfig,
sometimes it works sometimes it don`t. chkdisk, system diagnostic,
MBAM scans, MSE scans nothing helps. i`ve resolved myself to just
changing the zoom settings and go from there.
Hi Leo, I run a HP Envy reversible with windows 10. I have used this for a couple of years now with no problems, the other day just after a crucial update my screen went blue and that was that, it would not boot only offering a repair, the repair did not repair the trouble shooter didn’t know know the answer so I ased a computer man to come and fix it. He tried several things and then told me he was going to take it home where he had more testing equipment, he also said he would transfer all my docs, etc, to a external drive “which I supplied” and away he went. After several telephone calls that were unanswered he returned my pc switched it on and it booted up, he also sold me a small usb with a booting up system on it, he told me the pc would be faster to work on because all my personal stuff, photo’s downloads, documents etc, were on a external drive and I only had to plug it in and my data would be available and after I had paid him off he went. Every thing seemed to be ok I checked my mail on two accounts opened the news stations, played solitaire and switched the pc off. Sadly it would not boot up again just showed a repair, recovery option that didn’t work it all went in circles. I have emailed him but no reply has been received. So I plugged in my new usm boot up gadget and started the pc, it got to the restart offer and then it stopped and returned to the repair, rfecovery option. I then plugged in my boot usb and it went through the motions until the restart otion, I then unplugged the usb and carried on. I finished the new installation of windows 10, being helped by “the built in “cortana” voice, she seemed to know what she was doing, and my pc sprang to life. As before I checked my mail, etc, switched it off only to find it will not boot up again, it just show blue screen with repai, recovery, trouble shoot options etc. Can you help, please.
It’s not possible to diagnose a situation like that without a hands on inspection. It sounds like it might be a hardware issue since reinstalling Windows didn’t solve the problem.
I’d recommend finding another technician, I’m afraid.
Keith, this may not be a job for you, but check if your RAM modules are seated correctly. Remove them and install them again. Assuming you trust your computer guy, one reason he may have said to put all your files on an external drive may be because your disk (hard drive or SSD) is filled to capacity. Make sure you have at least 10GB free for Windows 10. Another reason you may be getting into repair mode is that your main drive isn’t set as the boot device.
Hi Leo, I have built my own desktops for years, one of the things I always do is turn my case fans so they suck air into the case instead of blowing out. I then put a filter on the outside of the case over each of the fans (so I can easily remove clean and or replace them when the get clogged). This way I have a “positive pressure” case and I’m not sucking dust into the box and the components in it. It has worked great for me for decades, I have even done the same to OEM desktops bought off the shelf, even if it meant grinding off riveted fasteners on the fans and replacing them with nuts and bolts just so I could turn the fans around and add a filter. You may have already done this yourself, or you may want to try it sometime. I worked for Big Blue for 35 years, and “negative pressure” boxes were very prone to packing the innards with dust and overheating. Cheers, and I love your news letters, thank you and keep them coming! 🙂
I’ve thought about adding a filter (like a coffee filter AND changing it daily) over my intake screens. Unfortunately, if I did this I’ll bet not enough air would enter the box. Your suggestion of reversing the fans (so it’s an intake fan) and adding a filter sounds better. I also put a piece of tape over my various card slots so dust and cat hair doesn’t go inside. My smoking at my PC doesn’t help either.
Hello Leo. My problem with my laptop (Toshiba Satellite) is that I keep losing my internet (wifi and/or ethernet) in addition to just freezing. What may be the problem? I have my laptop sitting on 2-fan laptop stand and it works. Thanks.
This feels like some sort of software/driver issue. Make sure you’re as up-to-date as possible, perhaps see if you can get newer networking drivers from Toshiba. If all else fails I’d probably try repairing Windows itself: https://askleo.com/five-steps-to-repair-windows-10-without-losing-programs/
i hold the power button for 30seconds it worker thank you good advise