Mac Performance

How to Speed Up Mac High Sierra

Want to know how to boost the speed up of macOS Sierra? It can be simple when adopting the following strategies:

  • Closing excessive apps
  • Performing a fresh OS install
  • Reducing your screen transparency
  • Decluttering your desktop
  • Utilizing monitoring tools
  • Leveraging Disk Utility
  • Clearing cache
  • Using third-party Mac optimization apps

Is your Mac running slow High Sierra, making it sluggish and less responsive than usual? Fret not, we've gathered a set of working solutions to supercharge your macOS experience. From excessive app closures to leveraging third-party optimization tools, our guide provides step-by-step instructions to revitalize your Mac's speed and efficiency. Say goodbye to lagging performance with these actionable tips.


Before we begin:


When it comes to boosting your Mac's performance on High Sierra, it's all about making smart moves rather than toiling away. Ever wondered why your MacBook isn't as snappy as you'd prefer? It might be time to tidy up your Mac storage.


Try MacKeeper’s Safe Cleanup—crafted exclusively for your Apple machine. This nifty tool works wonders by whisking away unnecessary clutter, freeing up valuable space, and giving your Mac’s system the performance boost it craves. With MacKeeper at your side, your device can get the VIP treatment it needs, effortlessly improving its overall stability.


Here’s how you can use MacKeeper’s Safe Cleanup to free up your system storage:

  1. Download MacKeeper and launch the app on your Mac.
  2. Navigate the side menu to the Safe Cleanup feature.
  3. Click Start Scan to allow MacKeeper to scan your device for unnecessary clutter, junk, and cache from your Mac.
  4. On the left, tick what you want to remove by clicking the button Clear Junk Files.

Why is your Mac High Sierra so slow?

Mac slowdowns on High Sierra often stem from the OS update demanding more resources, especially on older Macs. Over time, a number of factors can contribute to a sluggish Mac performance:

  • Ageing hardware
  • Full hard drive
  • Demanding background apps

How to make macOS High Sierra run faster

Is your macOS High Sierra feeling sluggish? Then catch our tips to make Mac High Sierra faster and enhance your Mac's efficiency.


Our recommended solutions to boost Mac High Sierra speed:

1. Close open app

Having issues trying to close an open app? To force quit open apps:

  1. Press Option + Command + Esc.
  2. In the pop-up window, choose the app you want to close.
  3. Click Force Quit.
  4. Confirm the action to close the application forcibly.
To close an open app to help speed up macOS High Sierra, you will need to begin by pressing Option + Command + Escape on your keyboard. This action will bring up the pop-up Force Quit menu.
Step 1. Press keys Option + command + Esc
To close a completely unresponsive app Mac High Sierra, you may need to Force Quit the app. When the pop-up window will then allow you to select which app you want to Force quit.
Step 2. Click on the app you want to close and press Force Quit

2. Reduce the tone of the visual effects

For another macOS Sierra performance improvement, why not try streamlining your Mac's visual effects and removing all those unnecessary visual effects? Follow the steps below to reduce motion and disable transparency of your macOS High Sierra system:

  1. Click on the Apple logo and select System Preferences.
  2. Click on Accessibility > Displays.
  3. Check the box beside Reduce Motion to decrease the motion effects.
  4. In this panel, you can also disable transparency effects and reduce display contrasts.
To reduce the tone of the visual effects to enhance the visual simplicity of your installed macOS High Sierra version, you'll first need to open System Preferences. Then click on Accessibility> Displays.
Step 1. Open System Preferences and click on Displays
You will now see a whole variety of options that you can cater to meet your motion and visual display preferences in a bid to help speed up macOS High Sierra version.
Step 2. Reduce the motion and visual effects of your Mac display

3. Сlear cache

Clearing the cache on your device might help speed up macOS Sierra. Here’s how to refresh your Mac:

  1. Open Finder.
  2. From the top menu, click Go > Go to Folder.
  3. In the window, type ~/Library/Caches/.
  4. Open folders with cache files, and click Move to Bin.
  5. Right-click on Bin and select Empty to free up additional space.
To clear cache in an attempt to help speed up macOS High Sierra, you'll first need to begin by opening Finder. Then click on Go > Go to Folder.
Step 1. In Finder click on Go and select Go to Folder
Once you've opened the Go to Folder on macOS High Sierra, in the window that pops up type in the following path ~/Library/Caches/.
Step 2. In the window type  ~/Library/Caches/
Now you'll be able to look for any cache files inside the folders on Mac High Sierra. Highlight any you find, right-click and select Move to Move to Bin.
Step 3. Identify unnecessary cache files and move them to Bin
To make sure the cache is removed from your device to help speed up macOS High Sierra, open your trash and click Empty Bin.
Step 4. Empty Trash to free up additional space on the device.

4. Clean hard drive

To speed up Mac High Sierra, clear your hard drive to get rid of any unwanted data and unnecessary junk files with our handy feature. To use MacKepeer’s Safe Cleanup for cleaning your system:

  1. Open MacKeeper and click on Safe Cleanup.
  2. Click Start Scan.
  3. Tick what you want to remove and click Clear Junk Files.
Cleaning your Mac hard drive could help speed up your installed macOS High Sierra version. The best method to ensure all junk and clutter is removed properly is to use a third-party app like MacKeeper, which can take care of the cleanup process for you. Just open the app and select Safe Cleanup.
Step 1. Open MacKeeper and select Safe Cleanup
Click start scan and let MacKeeper find any unnecessary logs, clutter, and junk that can be removed on macOS High Sierra. This can help clean our hard drive and therefore, potentially speed up your device.
Step 2. Click Start Scan
When the scan is complete on Mac High Sierra, tick what you want MacKeeper to remove and then click on Clear Junk Files to remove clutter from your Mac.
Step 3. Tick the junk and clutter you want to remove and press Clear Junk Files

5. Optimize storage

Optimizing storage to help make Mac High Sierra faster is easy. Here’s how to enhance your Mac’s system storage:

  1. Click on the Apple menu, then select System Preferences.
  2. In System Preferences, click General.
  3. On the right-hand side, click Storage.
  4. Open Storage settings to view recommendations on optimizing your Mac's storage.
 To optimize your macOS High Sierra storage, it's advised to declutter your device. To do this, begin by opening System Preferences and clicking on General.
Step 1. Open System Preferences and click General
From your General folder on Mac High Sierra, you'll be able to select Storage and look through the tailor recommendation to help you optimise your Mac's storage. These actions might help speed up macOS High Sierra.
Step 2. Select Storage and follow the recommendation to optimize your storage

6. Speed up Mac High Sierra startup

If you’re looking to improve your Mac’s startup speed, let us help you. To speed up Mac High Sierra startup:

  1. Open System Preferences.
  2. Click Users & Groups.
  3. Then select Login Items.
  4. Identify programs that aren't necessary during startup and uncheck to disable them.
To speed up a Mac with macOS High Sierra, it's a good idea to limit the amount of apps and programs you have loading each time you start up your Mac. To manage these programs, you'll first need to open System Preferences and click on Users & Groups.
Step 1. In System Preferences > click on Users & Groups
After clicking on Users & Groups, you'll be able to select Login Items. From here you'll be able to disable any programs or apps you don't need to load upon start-up in a bid to help speed up devices with macOS High Sierra installed.
Step 2. Select Login Items and review any programs to disable from startup


PRAM/NVRAM can be reset if your device needs a macOS Sierra performance improvement due to it acting up. To reset the PRAM/NVRAM:

  1. Turn on the Mac after a shutdown.
  2. During startup, press Command+Option+P+R.
  3. Hold keys until your Mac restarts and you hear the chime.
  4. Release keys.
If you want to speed up macOS High Sierra, then resetting PRAM/NVRAM is a good idea on macOS High Sierra. All you need to do is Turn on your Mac after a Shut Down. As soon as it powers up press Command + Option + P + R. Release when the final startup chime sounds.
Press Command+Option+P+R until the startup chime sounds, and then release.

8. Reset your SMC

Wondering what an SMC reset is? It stands for System Management Controller, and it's your secret weapon for tackling extreme MacBook slowness, battery issues, and certain hardware glitches, like fan problems. We strongly advise you to only consider this optimization step if our other solutions have failed to help speed up the Mac High Sierra.


Here’s how to initiate an SMC reset:

  1. Shut Down your Mac and make sure the power cord is connected.
  2. Turn your Mac back on while also holding down the keys Shift+Control+Option.
  3. Release the keys and allow your Mac to start up as usual.
To reset your SMC to help improve the speed of your device with macOS High Sierra, you'll first need to ensure you Shut Down your device and have the power cable plugged in.
Step 1. Shut Down your Mac and ensure the power cable is connected
Now, turn back on the Mac High Sierra whilst also pressing down the keys Shift+Control+Optoion. Let go of all keys and allow Mac to start up.
Step 2. Turn your Mac back on, whilst also holding the keys Shift+Control+Option

9. Reinstall macOS

If you're experiencing persistent speed or storage issues on your Mac, reinstalling macOS High Sierra can be a game-changer for speeding up your system. Be sure to check out our macOS version list to double-check device compatibility.


To reinstall your current version of macOS, follow these steps:

  1. Restart your Mac and hold down Command + R until the Apple logo appears. This opens macOS Recovery.
  2. In macOS Utilities, select Reinstall macOS and click Continue.
  3. Proceed by following the on-screen instructions. Choose your disk, confirm the action, and wait for the installation to complete.
To reinstall your current version of macOS High Sierra, begin by restarting your Mac and holding down the keys Command+ R. This will open macOS Recovery.
Step 1. Restart your Mac and hold down Command+R
In macOS Utilities you'll be able to select the option to Reinstall a new copy on macOS High Sierra. Once you click on Reinstall macOS, confirm the action and follow the on-screen instructions.
Step 2. Select Reinstall macOS and follow the on-screen instructions

Note from our experts:


We recommend you back up all of your important files before reinstalling macOS. This way, you’ll avoid any unplanned data loss during your efforts to speed up Mac High Sierra.

10. Upgrade your RAM

Looking to boost your device’s CPU for an overall enhanced user experience? Follow these steps to safely upgrade your RAM:

  1. Shut Down your Mac and remove its bottom case.
  2. If present, release the memory module by pushing the levers on the sides outward. This frees the module from the memory card slot.
  3. Insert a new memory module into the slot.
  4. Then carefully close the bottom case.

11. Update an SSD

If you want to go further and make Mac High Sierra faster, you can update an SSD (solid state drive). Here’s how to do that safely:

  1. Choose an SSD that aligns with your Mac's specifications.
  2. Prepare all the tools and materials required for the upgrade.
  3. Ensure the SSD is properly formatted for compatibility with your Mac.
  4. Copy the contents of your Mac's hard drive to the new SSD.
  5. Carefully detach the existing hard drive from your Mac.
  6. Integrate the new SSD into your Mac for enhanced performance.

Hint from our team: 


This step may not be necessary to speed up Mac High Sierra, but if your Mac is so slow, that it’s lagging, or crashing continuously, then it could still be a solution worth considering to speed it up.

Unleashing the full power of your Mac High Sierra

Speeding up Mac High Sierra involves more than just enhancing performance; it's about optimizing every aspect for a seamless user experience. The steps we’ve outlined in this guide can help unlock your Mac's full potential—from clearing the cache on your hard drive to hardware upgrades. These solutions can get your chosen macOS system running smoother and quicker.


MacKeeper's Safe Cleanup stands as the trusted tool that can assist you on your journey to optimize your Mac system and storage. It simplifies the decluttering process, efficiently removing redundant files and optimizing storage space. Consider it your dedicated ally, ensuring a consistently enjoyable computing experience with your high-performing macOS High Sierra.

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