It can be frustrating when your Mac runs hot or overheats. An overheating Mac may experience performance issues, shut down unexpectedly, or damage components if left uncontrolled. Fortunately, there are several steps you can take to help your Mac cool down.
Common Causes of Mac Overheating
There are a few common culprits that can cause a Mac to overheat:
- Dust buildup – Dust and dirt inside your Mac can obstruct airflow and cause components to heat up. This is a very common cause of overheating.
- Heavy computing tasks – Activities like gaming, video editing, 3D rendering, programming, etc. utilize your Mac’s hardware extensively and can cause the temperature to spike.
- Too many apps open – Having many apps and browser tabs running at once eats up RAM and CPU resources, increasing heat.
- Old thermal paste – The thermal paste between the CPU/GPU and heatsink can dry out over time, reducing heat transfer.
- Faulty fans – Malfunctioning or blocked cooling fans prevent proper airflow to carry heat away.
- Poor ventilation – Using your Mac on a pillow, bed, or other soft surface can block ventilation ports.
How to Check Mac Temperature
To see if overheating is occurring, you can use free apps like iStat Menus or HWMonitor to check your Mac’s temperature sensors in real-time.
Watch for temperatures over 90°C for the CPU and 80°C for the GPU. If you notice temperatures near or over 100°C, immediate action is required to cool down your Mac.
Where to Check Mac Temperatures
Apps like iStat Menus and HWMonitor provide temperature readings for critical components:
- CPU temperature – This is the main processor temperature and most important reading to watch. Idle CPU temp should be around 35-50°C.
- GPU temperature – The graphics card or GPU temperature. Watch for over 80°C.
- Hard drive temperature – HDD or SSD drives should run below 55°C.
- Battery temperature – Ideal battery temperature range is 15-35°C.
How to Cool Down an Overheating Mac
If you notice your Mac overheating, there are a number of troubleshooting tips you can try:
1. Quit Unneeded Apps and Browser Tabs
Heat often comes from an overloaded CPU/GPU. Try closing unused apps and browser tabs to free up processing resources and RAM usage. Fewer processes running reduces heat output.
2. Adjust Energy Saver Settings
Under Energy Saver settings:
- Set computer sleep to occur sooner when inactive
- Uncheck “Prevent computer from sleeping automatically when the display is off”
- Check “Enable Power Nap while plugged into a power adapter”
This allows your Mac to cool down more often in sleep mode.
3. Clean Dust Buildup
Use compressed air to spray out any dust accumulation in the cooling fans, vents, and heat sinks. This allows for proper airflow to cool components.
4. Elevate Your Mac
Place your Mac on an elevated cooling pad or stand. This allows air to flow underneath and prevents surfaces like beds or sofas from blocking ventilation.
5. Adjust Screen Brightness
A bright screen contributes heat. Try dimming your display brightness and auto-hide any menu bars.
6. Use an External Cooling Fan
Position an external cooling fan near your Mac to help force airflow. Avoid blowing air directly into vents.
7. Reset SMC and PRAM
Resetting the SMC and PRAM can clear any system issues causing abnormal heat. For MacBooks shut down, press left Shift + Control + Option + Power button for 10 seconds. For iMacs unplug, press and hold power button 10 seconds before replugging.
8. Check Activity Monitor
Use Activity Monitor to sort processes by CPU usage. Quit or force quit any runaway apps hogging CPU resources.
9. Update and Optimize Software
Install any pending macOS updates, firmware updates, and application updates. Also uninstall unneeded programs taking up CPU, RAM, and storage space.
10. Replace Thermal Paste
For older Macs, replacing dried out thermal paste between the CPU/GPU and heatsink can significantly improve heat transfer and lower temperatures.
11. Avoid Heavy Multitasking
When possible, focus on one demanding task at a time. Heavy multitasking with multiple apps can overwork your Mac’s components.
12. Check for Software Conflicts
Conflicts between two incompatible apps can cause excessive CPU usage. Try uninstalling problem apps or checking for software updates.
13. Adjust Power Settings of Individual Apps
Some apps allow setting Power Usage to “Lower energy impact” in settings to reduce heat. Chrome and Firefox, for example, have this option.
14. Take Your Mac to Apple
For persistent overheating or temperatures over 100°C, take your Mac to Apple or an authorized repair center. There may be an underlying hardware issue.
When to Be Concerned About Mac Overheating
As a general guideline:
- 50-60°C – Acceptable operating temperatures for a Mac under normal use.
- 60-80°C – Mac is running hot. Check for dust and heavy usage. Implement cooling steps.
- 80-99°C – Serious overheating occurring. Take immediate action to cool Mac and find cause.
- 100°C+ – Extreme overheating. Shut down Mac immediately and investigate issue or take to Apple.
Sustained temperatures in the 90-100°C range can damage internal components and lead to system instability and shutdowns. Keep an eye on your Mac’s temps and take quick action if you notice numbers creeping up.
Mac Cooling Tips and Best Practices
Implementing proper usage and maintenance habits can help prevent Mac overheating issues:
- Keep your Mac internally dust-free with occasional compressed air cleanings.
- Only run necessary apps – quit ones not in use.
- Avoid using your Mac on elevated or uneven surfaces that may block airflow.
- Adjust screen brightness to lowest comfortable level.
- Use dedicated GPU apps like gfxCardStatus to force integrated graphics when high GPU isn’t needed.
- Allow your Mac to properly enter sleep mode and cool off periodically.
- If gaming or rendering, use an external cooling fan to augment airflow.
- Check Activity Monitor for any runaway apps consuming CPU.
- Keep macOS and apps updated to latest optimized versions.
Implementing these best practices will keep your Mac running cool and prevent performance issues and system damage from excessive heat.
When to Take Your Overheating Mac to Apple
If you have persistent overheating and have tried the troubleshooting tips above without success, it’s a good idea to take your Mac into an Apple Store or authorized service provider for evaluation.
Signs that professional servicing is needed include:
- Fans constantly running at maximum speed
- Temperatures consistently over 90°C even at idle
- Unexpected system crashes or shutdowns
- Unusual noises coming from fans
- Obvious signs of dust buildup inside vents
An Apple technician can run diagnostics to check your Mac’s cooling system and identify any underlying hardware issues causing heat buildup. Some examples of repairs they can perform include:
- Applying new thermal paste between chips and heatsinks
- Replacing a worn out cooling fan
- Fixing obstructed air vents
- Replacing a faulty temperature sensor
- Fixing loose internal cables interfering with fans
It’s generally a good idea to take your Mac in yearly for a checkup and cleaning to prevent small issues from becoming big problems. Apple also offers flat-rate repairs for certain overheating issues that are out of warranty.
Summary of Fixes for an Overheating Mac
To recap, try these steps to cool down an overheated Mac:
- Quit unneeded apps and browser tabs
- Adjust Energy Saver settings for better sleep/wake behavior
- Clean any internal dust causing airflow obstruction
- Elevate your Mac for better underside ventilation
- Turn down brightness of display
- Use an external fan directed at Mac
- Reset SMC and PRAM to clear system issues
- Check Activity Monitor for high CPU usage apps
- Update macOS, apps, and firmware
- Replace dried-out thermal paste on CPUs/GPUs
- Avoid heavy multitasking
- Check for software conflicts
- Set intensive apps to Low Power mode
- Take Mac to Apple if overheating persists
Following proper usage habits and maintaining your Mac will also keep temperatures in a safe range. Be alert to the signs of overheating and take quick action to keep your Mac running in tip-top shape.