How to migrate essential information from a 2020 iMac to a 512GB Mini M4, excluding large files and folders?

Migrate manually:

Backup the old Mac to an external disk with Carbon Copy Cloner.

Install the newest supported macOS to the new Mac.

Go through every folder in the backup disk > your home folder and copy user data files to the new Mac' s home folders.

If you have important info in ~/Library (mainly Mail) don't forget to copy it. So if you use Mail.app, copy ~/Library/Mail to the Desktop (reveal that invisible folder via Shift-Command-. -- that is a period at the end). Then Mail > File > Import Mailboxes... > Apple Mail > choose that copied Mail folder > choose all Items and copy. Then on the left-hand-side under "On My Mac" > Import, ..., look for and move "Local" and all mailboxes inside it up under "On My Mac". Right-click and delete "Import" Mailbox (in my setup it has gmail mailboxes that are online anyway. YMMV).

Not all files will not fit to the new Mac. So make a folder for them in the backup disk and in the future use that. Don't forget to backup also the external disk.

Install any important 3rd party apps.

You can not fit a 1 gal. of water in a ½ gal. bucket.

Migrating to a new Mac is all or nothing.

You'll never be happy downsizing.

If you purchased the M4 Mac mini directly from Apple..?

You have 14 days to return the 512GB M4 Mac mini no questions asked.

Apple - Legal - Sales Policies - U.S. Retail Sales

Then buy a configure to order model with 1T or 2T of storage.

Buy Mac mini - Apple

media_lush wrote:

I recently had a look at the storage settings and two things stuck out - the spinning on photos and system data as well as 128gb on iCloud drive. I think this iCloud thing might be a big part of it as I cancelled my 50gb £0.99p storage per month as I was fed up with the almost daily emails suggesting more storage... the thing is I was on 49gb or so and attempted to get rid of a few files with no success and I have no idea why double that amount is showing up...any idea how to just dump everything and start again?

You can not rely on that eye candy bar or the categories for accurate Storage totals.

It used to work great with older macOS versions up to around Monterey, but has been seriously getting worse in later macOS versions.

also any idea why the spinning to find the total amount?

You will be lucky to get a total for System Data and/or anything that is in iCloud limbo land.

I'll dump the iOs back up as I can just do a new backup.... there's definitely something squirrely going on.

Agreed.

Sadly it sounds like you're going to have to trim a lot more from the old Mac's internal storage, then make a new backup to migrate from.

Plus what you need to do, is use Disk Utility instead of System Storage to check the old Mac for total space used.

Again, this is why I suggested returning the 512GB model for one with larger storage.

How much more of your own time and focus do you want to spend here, trying to fit most of twenty pounds of stuff in a five pound bag?

This task also usually doesn’t stop. You’ll be managing any (lack of) storage on an on-going basis too, and for as long as you are using this Mac, too. (When I tried this, I ended up with files scattered all over the place on external devices and on removable USB sticks, which meant finding those files later (and ensuring the files were all at least occasionally backed up) was itself a project. And it meant I lost some of it.)

Your easiest options here are either installing and using an external storage device as your boot and home device, or returning this Mac in the 14 day window and get a Mac with storage commensurate with your current and likely future needs.

Or it means going all-on on iCloud, enabling iCloud Drive Files and Documents — what has been called iCloud Desktop — and storing everything there. But that means renting a terabyte or two from Apple.

Delete everything you don’t want and can’t fit off the old Mac (and more, yep, and yet more), and then transfer.

Otherwise, perform a clean install on the new Mac, boot it and enable system security to allow an external boot, then install a 2 GB or larger SSD external, install macOS on that, and boot and use Migration Assistant or Setup Assistant to load that.

Or return the Mac, and get one with sufficient storage for your usage.

If you had 128 GB stored on iCloud Drive, but were only paying for 50 GB of space, it’s no wonder that you got reminders to add more space.

But removing all of that data from iCloud while keeping local copies would not make it take up 0 bytes on your computer.

Re: “I've decided to go the 'buy a 3rd party 2TB chip route'”

The flash chips in the M4 and M4 Pro Mac minis may be on their own board, but the contents of those chips are normally encrypted; kept in sync with keys stored within the M4 or M4 Pro chip.

Even if you avoid physically damaging your Mac mini in the process of replacing the internal flash chips (an act that will void the warranty), you will be turning the Mac mini into a “brick” unless you have some way of getting the new flash chips properly loaded.

Don’t say that you weren’t warned.

Fitting a third party SSD is the worst idea in the world and you stand a good chance of turning your Mac into a doorstop!

The answer is dead simple.

Buy a 2TB NVMe from Amazon for around £100, install macOS on it and boot your Mac from that.

Although the drive will be slower than the internal you will never notice any difference in performance (except in the rare occasions you may be copying 100GB files, which will obviously take a bit longer.

This is what I have done with my M2 and M4 minis.

With my M2 I bought an old type SATA SSD and a USB 3.0 enclosure - extremely slow drive. Tests between that and the internal SSD showed that subjectively there was no difference in the feel of the computer, it was just as snappy editing 4K in FCP and scored almost identical results in the GeekBench test. It took slightly longer rendering or exporting but it was less than 5% which equates to an extra 3 minutes in a 60 minute procedure.

I later bought an NVMe in a Thunderbolt enclosure . . . much faster and vastly more expensive. However, the computer handled exactly the same except the rendering and exporting were a tad faster being identical to the internal SSD.

Since then I have bought a 2TB NVMe in a USB-C enclosure which is midway between the SATA and the Thunderbolt in actual speed but which is virtually identical in performance to the internal, so from now on I will only be getting USB-C enclosures as they are much cheaper.

Incidentally buying computers on eBay is not a good idea.

John Lewis (one of the most reputable stores in the world) sells the M4 mini with a 512GB SSD for £699 and you get a 2 year warranty thrown in.

Buy a 2TB NVMe (Crucial, SanDisk, Integral etc.) in a USB-C enclosure for around £100 from Amazon . . . problem solved.