My system

[Kellie W]

Hi Brian & Damien

My iMac has been acting up. My hubby bought it for me (a surprise) for my birthday in 2019. (He consulted with someone and ordered it special from Apple). It had been working great until it automatically upgraded to Big Sur. Now I get what seems like daily updates etc. etc. It is a (hold my breath) 21.5" iMac. (I have read your 2020 posts about 21.5" iMacs; too late to turn back now). Details attached. Since I updated to Big Sur the fan runs ALL the time. Also the system seems to take about 8-10 minutes to boot up. (I shut down when I am done each time). Also PS doesn't run so well any more, it also takes a long time to boot up along with Bridge. Both freeze if I open too many photos at once. I am running PS CC 2021 and Bridge 2021. With the exception of internet and mail I don't use this system for much else.

How can I fix the fan and speed things up again?

 

 

[Kellie W]

Apple store (closest) is a 100 minute drive ( one way). Not happening in a pandemic and in current lockdown.

[Brian]

Ugh. You aren't going to like my answer.  

Oh, you have a Fusion Drive. That's part of the problem. Honestly, I think you will more than likely have to "Nuke" the HD (Format and Reinstall) and put on MacOS Catalina. Chances are, the Genius Bar is going to have to do it since Catalina is not longer available, at least online. Alternatively, you can call Apple and see if they can get you a download link so you can create a Bootable Thumbdrive.

Upgrading to Big Sur is mostly a one-way proposition. There is no going back at this point, other than formatting and reinstalling everything. The only other way, is if you had a Time Machine Backup that was un-touched by Big Sur. Then it's plausible to boot in Diagnostic Mode, Format your Main HD, and then re-install from the Catalina Time Machine Backup.

Those are your choices. I wish I had better info for you. Either way, I'd schedule an appointment with the Genius Bar if you can. The AppleStores are kinda weird now with COVID-19, so make sure you schedule an appointment.

[Kellie W]

Ugh. Thank you Brian for your comments. Well there is nothing I can do now except uncheck automatic updates. (Which somehow got magically turned on.)  Sigh... We are in a min of 28 days serious lockdown. Apple store is in a mall and malls are closed. Plus the Apple store's city it is in is a hotspot and no where I want to go. Unfortunately, this is not something for me to do on my own despite probably having a time machine back up of Catalina. Thank you for the reply.

Happy Holidays.

[Brian]

There is hope for you yet! A member on FB Ask Damien Linked to this Article:

Downgrade MacOS Big Sur

Now, you will need a Catalina Time Machine Backup to restore from, OR you can create a Bootable Catalina Thumbdrive, boot your Mac into Diagnostic Mode, format the Macintosh HD and then install Catalina. Of course, this method will nuke everything on your Main HD, but it should help with your performance issues and you will get your Mac back. Might be worth the hassle instead of the long drive.

[Kellie W]

The article was by Macpaw. Is that true that Clean my mac x is ok to use? An Apple genius told me to remove it before. Just want to ensure there is no conflict of interest.

[Brian]

I use CleanMyMac weekly and have been since 2009.  I highly recommend it. 

[Brian]

Apple will blame anything that isn’t installed by Apple. They will blame the extra 3rd party RAM that you installed as the reason that you mouse batteries died. Seriously. CleanMyMac is available on the App Store I believe, but I will need to check this. 

Now the program called MacKeeper, THAT PROGRAM IS EVIL. Don’t ever install MacKeeper. 

Everything that CleanMyMac does you can do by hand yourself. Especially if you leave it at the defaults. It’s just easier and safer to use CMM.