Crashing/Freezing Mac (Intel)

Firstly, if you can log into the Mac, make sure it is running with the latest software updates. You can check this by going into System Settings → General → Software Update

Next, if you do have AppleCare+ it’s probably best to utilise it - it’s what you paid for after all!

Safe Mode

  • See if running in Safe Mode is better. If so, then there may be a problem with some sort of third-party piece of software that is causing the issues.

  • To access Safe Mode, hold Shift down while pressing the power button. You may need a wired keyboard rather than one that works through a Bluetooth or wireless dongle to do this.

  • For crashes, access the Crash Reports, which should list the name of the application causing the crash.

    • To do this, open Console and then on Crash Reports. You can then try either updating the software, letting the developer know of the crash, or uninstall the application.

    • Next, uninstall recently installed applications, because if your Mac was running well until recently, these are most likely the culprits.

Hardware Issues

Overheating

  • Diagnosing overheating is a bit more difficult to do as there is no easy way to check this within Macs. As such, you’ll need to install an application like Fanny, which will reside within your Notification Centre and Menu Bar, informing you of CPU and GPU temperatures, as well as the speed of any fans.

    • Compare the temperatures to what your Mac model ought to be running at. If the temperatures are exceeding normal operating values, it might be worth:
      • First checking if there is a built up of dust in or around any vents, try and clean these out using compressed air.
      • Secondly, try to increase airflow by placing the Mac on a hard surface with plenty of room around it, and away from direct sunlight or any other sources of heat. Cooling pads placed under the Mac may also help.
      • Next try reducing the amount of pressure on the resources, so close unnecessary applications, and reduce screen brightness if you’re on a laptop.
      • If the fans are not running at the correct speed according to your Mac model, these may need replacing. iFixIt’s website has guides on how to do this for various Mac models, but you might need to have it repaired by a professional, and you should make sure such a repair does not invalidate any warranties.
      • Another possibility to overheating is that the thermal paste may need replacing. While there are guides on how to do this, it may be a task best undertaken by a professional due to its complexity, also checking again about any warranties not being invalidated.

Resources

  • Check your Mac’s resources, it might be being pushed beyond its capacity and thus causing issues.

  • To check this, open Activity Monitor and check the CPU Load (and how much is idle) and RAM Pressure (how much physical memory is available and how much memory is used). If you find the CPU load is high, and/or that you don’t have much RAM spare, this may be the cause of the problem.

  • In this case, either reduce the amount of running programs (or switch to programs which use less resources), or if it is a RAM issue, you might be able to upgrade your RAM.

  • However, upgrading the RAM may invalid a warranty, please be careful and check your warranty status before upgrading. Good guides to upgrading RAMs on various Mac devices can be found on iFixIt’s website here.

Disk Space

  • Check if you have enough disk space. If you have large files, see if these could be moved to an external drive. It’s also a good opportunity to uninstall old software you may not be using any more.

  • I recommend uninstalling with AppCleaner, which will try to make sure no unnecessary are left behind during uninstallation.

Malware

  • Check for malware issues. If you do not have an anti-virus installed, MalwareBytes have a free version here which can be used to help clean up infections, or just give you a peace of mind with a scan to see if the device is infected or not.

Time Machine

  • If the problem started recently, and you have Time Machine set up, you might want to use it to go back to a point before the issues began.

Fresh Install

  • If the issues continue persisting, you might consider reinstalling the operating system and start from a blank slate (with your important files backed up for course!).

  • To do this, access Recovery Mode by booting the device whilst holding down Command and the letter R at the same time. You may need a wired keyboard rather than one that works through a Bluetooth or wireless dongle to do this. Then, depending on your operating system, you should see the option in Utilities to reinstall.