How-To Geek

Diagnose PC Hardware Problems with an Ubuntu Live CD

So your PC randomly shuts down or gives you the blue screen of death, but you can’t figure out what’s wrong. The problem could be bad memory or hardware related, and thankfully the Ubuntu Live CD has some tools to help you figure it out.

Test your RAM with memtest86+

RAM problems are difficult to diagnose—they can range from annoying program crashes, or crippling reboot loops. Even if you’re not having problems, when you install new RAM it’s a good idea to thoroughly test it.

The Ubuntu Live CD includes a tool called Memtest86+ that will do just that—test your computer’s RAM! Unlike many of the Live CD tools that we’ve looked at so far, Memtest86+ has to be run outside of a graphical Ubuntu session. Fortunately, it only takes a few keystrokes.

Note: If you used UNetbootin to create an Ubuntu flash drive, then memtest86+ will not be available. We recommend using the Universal USB Installer from Pendrivelinux instead (persistence is possible with Universal USB Installer, but not mandatory).

Boot up your computer with a Ubuntu Live CD or USB drive. You will be greeted with this screen:


Use the down arrow key to select the Test memory option and hit Enter. Memtest86+ will immediately start testing your RAM.


If you suspect that a certain part of memory is the problem, you can select certain portions of memory by pressing “c” and changing that option. You can also select specific tests to run.


However, the default settings of Memtest86+ will exhaustively test your memory, so we recommend leaving the settings alone. Memtest86+ will run a variety of tests that can take some time to complete, so start it running before you go to bed to give it adequate time.

Test your CPU with cpuburn

Random shutdowns – especially when doing computationally intensive tasks – can be a sign of a faulty CPU, power supply, or cooling system. A utility called cpuburn can help you determine if one of these pieces of hardware is the problem.

Note: cpuburn is designed to stress test your computer – it will run it fast and cause the CPU to heat up, which may exacerbate small problems that otherwise would be minor. It is a powerful diagnostic tool, but should be used with caution.

Boot up your computer with a Ubuntu Live CD or USB drive, and choose to run Ubuntu from the CD or USB drive. When the desktop environment loads up, open the Synaptic Package Manager by clicking on the System menu in the top-left of the screen, then selecting Administration, and then Synaptic Package Manager.


Cpuburn is in the universe repository. To enable the universe repository, click on Settings in the menu at the top, and then Repositories. Add a checkmark in the box labeled “Community-maintained Open Source software (universe)”.


Click close. In the main Synaptic window, click the Reload button. After the package list has reloaded and the search index has been rebuilt, enter “cpuburn” in the Quick search text box.


Click the checkbox in the left column, and select Mark for Installation. Click the Apply button near the top of the window. As cpuburn installs, it will caution you about the possible dangers of its use.


Assuming you wish to take the risk (and if your computer is randomly restarting constantly, it’s probably worth it), open a terminal window by clicking on the Applications menu in the top-left of the screen and then selection Applications > Terminal.

Cpuburn includes a number of tools to test different types of CPUs. If your CPU is more than six years old, see the full list; for modern AMD CPUs, use the terminal command


and for modern Intel processors, use the terminal command


Our processor is an Intel, so we ran burnP6. Once it started up, it immediately pushed the CPU up to 99.7% total usage, according to the Linux utility “top”.


If your computer is having a CPU, power supply, or cooling problem, then your computer is likely to shutdown within ten or fifteen minutes. Because of the strain this program puts on your computer, we don’t recommend leaving it running overnight – if there’s a problem, it should crop up relatively quickly.

Cpuburn’s tools, including burnP6, have no interface; once they start running, they will start driving your CPU until you stop them. To stop a program like burnP6, press Ctrl+C in the terminal window that is running the program.



The Ubuntu Live CD provides two great testing tools to diagnose a tricky computer problem, or to stress test a new computer. While they are advanced tools that should be used with caution, they’re extremely useful and easy enough that anyone can use them.

Trevor is our resident Linux geek, but always keeps his eyes open for neat Windows tricks too.

  • Published 05/5/10

Comments (14)

  1. nakuls

    It also tells you automatically if the hard drive has bad sectors. happened to me once i left client’s computer running idle for an hour(on live cd session) while i was doing some other work. notification popped up saying this hard drive may have bad sectors.

  2. mike

    i used this method many times before i heard of this not really in this way but wen it just wouldnt get out of that boot loop or i kept getting that blue screen of death i would just pop in that live cd and just install it and it would be great then i could go onto installing anything i wanted on the hd

  3. Cheap Hard Drive

    Have used cpuburn before and was quite impressed with it. I’d recommend it if you are having problems with your hardware as it’s pretty straightforward to use.

  4. David Levine

    Memtest86+ works like a charm. I was trying to install Windows XP on my mother-in-law’s PC and it would always fail at one part. I ran this program and found out that one of the memory sticks was bad. After replacing it, everything worked great.

  5. Michael J. Welch

    Which version of Ubuntu are you using? I just tried this with 10.04 and the boot screen looks completely different – There is no “Test Memory” option. All I see are the run and install options.

  6. Trevor Bekolay

    @Michael J. Welch

    In this article, it’s Ubuntu 9.10. I can’t imagine why they would take memtest off of the 10.04 live CD — this bug confirms that the functionality is missing, but no one has replied to explain why or how that happened. Hopefully it gets rectified soon — for now, you can use a 9.10 Live CD.

  7. Gill Bates

    i noticed cpuburn isnt in 10.04 either, any idea when they will fix that? or if i can do it myself? i hope so because i like it way better than 9.10 and i use these programs a lot for troubleshooting broken computers at my job

  8. Joris

    No the functionality isn’t missing, but you need to press Esc when the disc starts

  9. keith waller

    Your article omits some vital information, in that an instance of burnP6 need to be run per core to obtain a full system loading

  10. frances

    I am having a problem, two accually and was wondering if this program can diagnoise all hardware problems. My computer is making a clicking noise when it boots up the sound is simular to pressing the f8 key when going into safe mode. Also my volume keeps turning itself off upon start up. If this program won’t address that please suggest one. Thanks!! or should I say Help!!!

  11. Dinesh

    @frances backup your data the clicking sound from Harddisk is a sign of its death. you can use Ubuntu’s disk utility option to check harddisk.

    My problem my PC started restarting whenever an application is started so i started with Ubuntu Live 10.10 but i got the kernel panic message so i realize that RAM is having problem so i got another 2 RAM and now used 9.10 so i can do Test memory so started with first new RAM, Ubuntu 9.10, memtest86+ test there was no error message till 36% but after that PC shuts down tried 2 more time same result so put second RAM to test and same result.

    So whats the problem is my motherboard, or power supply is having problem till will save my time to figure out where’s the problem let me know guys. thanks.

  12. Shane

    So what happens if a pc beeps more than 3 time.
    is it the cpu ?

    and the last thing is when the pc does not show screen what can be the problem? cause i have tryed using 4 different screen cards but still no visual can it be the motherboard?

  13. nasr saad

    افادكم الله

  14. Andrew

    I came on on here to report what Keith also found. You must run an instance of this for each of your cores. So for a dual core CPU – run two instances. Otherwise the test is no good, only tests the one 1 core – which is really like 50%.


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