Test software for the Mac: Tool collection for component tests

An Apple Mac consists of various hardware components. In addition to the mainboard, processor (CPU), graphics card (GPU), working memory (RAM), hard drive, etc., the iMac and MacBook also have a display. Ideally, everything works as it should. But if you suspect a mistake somewhere or want to check the same before selling / after buying your Apple computer, there are various apps for this. Most of the test software for the Mac that you can use to run a hardware test is free. There are also free web offers directly in the browser. You can find a collection of tools here.

An Apple Mac, iMac and MacBook are made up of different components. You can test, read and analyze individual hardware with the apps, websites and system solutions shown here. Photo: 2019 MacBook Pro teardown from iFixit.com

An Apple Mac, iMac and MacBook are made up of different components. You can test, read and analyze individual hardware with the apps, websites and system solutions shown here. Photo: 2019 MacBook Pro teardown from iFixit.com

Check your monitor, iMac, or MacBook display for dead pixels

Pixel errors are individual pixels (e.g. individual LEDs in a screen) that do not work or do not work properly. A pixel error in the display of an iMac or MacBook is present when individual pixels display the wrong color, only black or only white when displaying the system, apps, pictures, videos and the like. 

As free test software for screens and monitors, macOS Inspect at. In addition to the "Dead Pixel Test", the app also offers a keyboard test (see next paragraph). If you want to display individual colors via the web browser, then there is the Eizo Monitor Check the right solution - also for sharpness, gamma, reaction and other tests.

  • Inspect download via GitHub: Click here
  • Eizo Monitor Check directly in the web browser: Click here

Check internal and external keyboards on Mac, iMac and MacBook

As mentioned above, you can use the Inspect app to check your keyboard and its individual functions. However, you don't need a third-party app if you just want to check the function of each individual button. So if you think that individual buttons defective or if you want to exclude this before selling / giving away the device, this also works via board funds. Under macOS you proceed as follows:

  1. Click on that Apple icon () in the macOS menu bar
  2. Opens the System settings ... and in it Keyboard
  3. Places in the tab Input sources the checkmark at "Show input sources in the menu bar"
  4. Click on the menu bar icon and then on "Show keyboard overview"
  5. Now press individual keys - If they are marked on the overview, they work
The macOS keyboard overview. The Command key and Shift are outlined in red because I held them down for the screenshot.

The macOS keyboard overview. The Command key and Shift are outlined in red because I held them down for the screenshot.

Check MacBook battery - read out battery status

Here in the blog already presented several times and is a really recommendable tool for monitoring the MacBook battery coconutBattery. This tool for the Apple Mac is also available in a free version (with fewer functions) and in a paid full version. However, both issue a diagnosis for the battery and can do this not only for the MacBook, but also for a connected iOS device, such as the Apple iPhone. In the full version, this even works via WLAN. You can find details about the program in this post.

A few data such as the remaining charge in mAh, the previous charging cycles, the voltage in mV, a status information (e.g. "Service recommended" for batteries to be replaced) and the like can also be obtained from macOS board means. To do this, simply use the following information from the system:

  1. Click on that Apple icon () in the macOS menu bar
  2. Select the menu item About this Mac
  3. Click on the “System report…” button in the “Overview” tab
  4. Select "Power Supply" in the hardware list (left)
  5. You can now find all the data in the info overview (right)
The battery status of my Apple MacBook Pro from 2012.

The battery status of my Apple MacBook Pro from 2012.

Check the function and status of internal and external hard drives

With a mechanical HDD hard drive, there is usually the option of reading out its status using the SMART function. That stands for "Self-Monitoring, Analysis and Reporting Technology". The hard drive automatically collects and stores data on functioning and defective units as well as failures and the like. This applies to both internal and external storage media. I already gave you an analysis tool for this three years ago Smart Alec presented.

SSD hard drives that use flash memory to write and read data can also use the SMART function. A possible failure of a solid-state drive inside or outside the Apple Mac can also be predicted. In order to check the hard drive status, there are also Smart Alec next to the aforementioned Smart utility or DriveDx ready. There are free trial versions of both as well as paid full versions.

Mac processor test - load the CPU and fan in a controlled manner

The processor or CPU (Central Processing Unit) is the component of a computer that is mainly responsible for processes and thus for the execution of the system, commands, apps and more. Several cores with a certain speed are available for this, depending on the processor, type and generation. Therefore, older Macs are more stressed by newer systems and programs than current models.

You can perform a CPU stress test on the Apple Mac without an additional app, for example in the terminal, by entering this command and confirming with Enter:

yes> / dev / null

In order to deal with several cores of the CPU, enter the command several times and confirm it after each entry. In order to be able to adjust the number again and again, use individual tabs in the terminal (in the menu bar on Shell -> New tab click). You can monitor the CPU usage in the Activity indicator. You end the stress test by closing the terminal or individual tabs with the above command.

If you do not want to use any commands in the terminal, a CPU test can also be carried out using various specially designed apps. An example of a stress testing tool is Prime95which, in addition to the Apple Mac, is also available for Windows PC, Linux and other systems. It is a free open source program that not only loads the CPU, but does so to convert Mersenne prime numbers (Declaration) to find. 

Somewhat more modern and specially designed for the CPU test Cinebenchtargeting graphics performance, but measuring CPU performance rather than GPU performance. This is sometimes confused in other guides on CPU or GPU tests.

What individual observations mean during the CPU test:

  • The fan works faster, but is only at its maximum after a few minutes: Everything is apparently okay
  • Fan turns to maximum immediately: the CPU thermal paste has dried out, the fan control is defective or the fan is gathering dust
  • Fan does nothing and the computer gets hot: Fan control or fan defective (Mac will then probably switch off if it overheats)

Mac graphics card test - check GPU for maximum performance

Like Mac devices themselves, graphics cards have a long service life if handled well. Except for some models or production lines of MacBooks, often in the range of 15-inch models. If you want to check the Apple notebook or another Apple computer for this component, the tool will help you Heaven further. It tests graphics cards on macOS, Linux and Windows. The following models in detail: ATI Radeon HD 4xxx and higher, Intel HD 3000 and higher and NVIDIA GeForce 8xxx and higher. Details and the free download you can find here.

Mac memory test - track down RAM errors in detail

In some Mac models, especially the MacBook, the RAM can be soldered into place. Defects lead directly to a loss of value or to the fact that a new purchase is more economical than a repair. It looks different with iMac, Mac, Mac mini and Co. - there are sometimes quite simple solutions to replace RAM bars and thus to fix errors in the main memory. 

To do this, you have to find it first - and help with it Rember. The test console works with Mac OS X 10.5 and newer versions of macOS. Also recommended by different sources MemTest86, which is booted from a USB stick and addresses the main memory with various algorithms. It is therefore ideal for support people who need to find faults on other people's computers.

All-in-one solutions: system monitoring with one app

Testing individual components and checking them for their functions makes sense if you suspect or want to rule out a fault in each of them. However, it can also be the case that the entire computer - including the hardware temperatures, the fan speed, etc. - should be monitored. And that's exactly why there are different solutions. Here in the blog I presented you with a practical tool for this in both 2018 and the beginning of 2020. With these links you can find information, tests and screenshots about HWSensors / HWMonitor and Sensei:

Apple hardware test or Apple diagnosis as a complete solution

In addition to the many apps, system tools and websites shown, there is also an option for which you only have to press two buttons. Because if you hold down the D key immediately after switching on the Mac, the will start Apple hardware test (Mac models up to early 2013) or the Apple Diagnostics (Mac models from mid 2013). 

After selecting the language, a loading bar appears showing the progress. When the analysis of the computer hardware has been completed, an overview of the data and sensor information is output. If an error occurs, it is usually displayed as an error code. You can google what the individual codes mean or ask support. You can find more details in this guide: Apple Hardware Test - Detect technical problems on the Mac.

More advice and help articles on the topic:

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  1. Marty Schellman says:

    Great and informative article, of great value to anyone troubleshooting their Mac. Thanks a lot for this!

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