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Why is macOS Catalina slow or very slow?

macOS Catalina can be slow or very slow for a few reasons, the main reason why macOS Catalina becomes slow is a Macintosh HD hard disk storage volume that has become, slow, this will make macOS Catalina also slow. Other reasons also include having malware infection on the Apple Mac computer.

Apple MacOS Catalina Support for Slow Apple Macs.

  • Do you need to know why macOS Catalina is slow or very slow?
  • Is your Apple MacOS Catalina Apple Mac computer slow or very slow after you have upgraded to macOS Catalina?
  • Do you need know how to speed up macOS Catalina on your Apple iMac computer or on your Apple MacBook Pro laptop computer?
  • Has macOS Catalina suddenly become slow on your Apple Mac computer?

If your Apple MacOS Catalina operating system is slow or very slow after upgrading to MacOS Catalina there are many reasons why. 

Did you know that by using a SSD solid state drive is one of the best ways to speed up macOS Catalina.

If you have a Apple Mac computer that is 2014 or newer, upgrading to macOS Big Sur can speed up a Apple Mac computer that is running slow on macOS Catalina!

Our Apple Mac computer engineers and Apple Mac computer specialists are able to help with the performance of macOS Catalina. Read our free guide about macOS Catalina and how to improve the speed and performance of macOS Catalina.

Apple MacOS Catalina Information.

  • A new Apple MacOS operating system is available each year, this can affect the performance of your Mac.
  • All Apple Mac computers that are manufactured from 2012 to 2019 can run Mac OS Catalina.
  • 7th October 2019 Apple launched MacOS Catalina to replace MacOS Mojave.
  • The next new release will be late 2021 with MacOS Big Sur.
  • Catalina may not be supported on any 2013 or newer Apple Mac computer once Big Sur released.

For the majority of customers, the Apple MacOS Catalina operating system simply runs at a very good speed.

But this is with an Apple Mac computer that has a SSD Solid state drive!

Did you know that Apple designed macOS Catalina and newer macOS to work much faster on a SSD solid state storage volume!

Why is macOS Catalina slow on my Apple Mac computer?

So, we need to ask why is Apple Mac OS Catalina slow on some Apple Mac computers?

The main reason why macOS Catalina is slow on some 2012 or newer Apple Mac computer, is that the computer has never had any Apple Mac computer maintenance done, or the internal storage volume has so many files, and folders, which is a key factor why a Apple Mac computer that is running macOS Catalina become slow or very slow.

Apple MacOS Catalina Memory Requirements.

The main reason that the Apple MacOS Catalina is slow or very slow is not enough memory.

After the Apple MacOS operating system has been upgraded, often a lack of memory, can cause slow performance.

Technically Apple says Apple MacOS Catalina runs on 4Gb memory.

Our Apple Mac engineers simply do not agree and 8Gb of memory is recommended, hence all new Macs have 8Gb memory now.

If an Apple iMac computer has 4Gb of memory and was running Apple Mac OS Yosemite without any problems, 4Gb of memory is ok.

Once a 4Gb Apple iMac computer is upgraded to Apple MacOS Catalina from Mac OS Yosemite or from MacOS El Capitan, a iMac can become slow or very slow.

This is because 4Gb of memory is simply not optimised for the newer Apple MacOS operating system software version installed.

And by design Apple wants customers to purchase a new Apple Mac computer, so they keep the memory requirements at 4Gb. 

Most Apple customers simply choose to then purchase a new Apple iMac computer to resolve the problem.

However, some Apple iMac computers, and Apple MacBook Pro laptop can be upgraded from 4Gb to 8Gb memory.

How to optimise MacOS Catalina Performance.

The solution is more memory, it may be possible to upgrade the Apple iMac memory from 4Gb to 8Gb or even 16GB.

This will make Apple MacOS Catalina much more responsive, why, the more memory installed from 4Gb makes a big performance boost.

This is not the only reason; the storage volume may be fragmented after the Apple Mac OS operating system software upgrade.

Or the Apple iMac computer is simply indexing the hard disk with Apple Spotlight.

Advanced MacOS Catalina Troubleshooting.

IF you have 8Gb of memory and you still have a slow Apple iMac computer after the Apple MacOS Catalina upgrade?

A third-party Apple Mac computer application can cause the Apple iMac computer to run slowly or very slow.

A Apple Specialist will look at Adobe, Microsoft, Anti-Virus and out dated Mac utilities and simply update or remove.

MacOS Catalina Third Party software applications update.

By reviewing the installed third-party applications that are installed on your Apple Mac computer can help.

The best possible performance can be achieved by making sure that all of your third-party applications are upto date.

Slow 1Tb SATA iMac Drive.

Apple iMac computers that have a iMac with a 1Tb SATA hard disk drive, the performance can be extremely slow.

Why? When Apple manufactured your once new Apple iMac computer, they use different vendors for the internal storage volume.

Some Apple iMac computers that have a 70% full storage volume and are using a Seagate or Western digital 1Tb SATA drive, can become slow after a MacOS Catalina upgrade.

Is your Apple iMac suddenly slow?

A Apple iMac computer can suddenly become slow or very slow, due to the internal design of the storage volume.

A solution for some customers would be to simply use Apple Time Machine to backup the Apple iMac computer.

And then restore the iMac to see if this helps resolve a slow Apple Mac running Apple MacOS Catalina.

iMac storage maintenance.

If the internal storage volume becomes slow either before or after a Apple MacOS upgrade.

Simply use the built in MacOS Catalina tools to review how much data is stored on your internal storage volume.

This can help resolve the slow performance of your Apple Mac computer.

For The Ultimate iMac Performance Choose SSD upgrade.

  • For the ultimate performance of Apple MacOS Catalina simply upgrade the Apple Mac computer to 8Gb.
  • Replace the Internal storage volume from a slow mechanical SATA drive to a faster solid state drive, SSD.
  • A 2Tb SSD solid state drive is the best option for a 1Tb mechanical storage volume replacement.

Catalina Computer Maintenance.

Our Apple Mac computer maintenance engineers can help optimise the speed and performance of your Apple Mac computer.

  • Keith Thomas is a Apple Specialist and a Apple Mac computer engineer, that worked for Apple Computer UK.
  • And now provides a professional Apple IT Support service for home users, small business, self-employed, companies.
  • We can help you with optimising your Apple Macs computer storage capacity.
  • Our Apple Mac Catalina Apple specialists can help you troubleshoot a slow Apple Mac computer.
  • We can simply perform this service by Apple Mac Remote IT Support service.

To speak to one of our Apple Mac computer engineers, or to arrange for a Apple Mac computer performance review.

  • Complete the online website contact form. (open 24 Hours) with 10:30 am to 21:00 pm response times for completed forms sent to us.
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