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allan.nyholm

macrumors 68020
Original poster
Nov 22, 2007
2,331
2,622
Aalborg, Denmark
Hello,

I'm in a bit of a situation where I don't know if my iMac from late 2015 is simply too slow to have Big Sur running on it.

The first sign of this I noticed early on with some of the Public Betas of Big Sur and now even the release version of Big Sur: 11.0.1

As the title implies, I've made a USB installation media on a Kingston USB 3 key, of which I have 3 of the same brand and appearance in 16GB, 32GBand 64GB sizes and used the official createinstallmedia command that I've done on the previous releases of macOS dating at least back to High Sierra for me.

What I'm experiencing is a really sluggish interface when first booted in to the Big Sur install media or even if I have gotten Big Sur installed; the Recovery partition of same.

I admit to having a setup that is made up of an external Thunderbolt SSD in an LaCie Rugged Thunderbolt/USB case as I have the iMac from that time that made use of only an internal 7200RPM 1TB HDD - I wasn't satisfied with that in the long run, so I made a purchase on the LaCie Rugged that has now a Kingston A400 SSD in it.

Now, my Mojave and Catalina USB installation media that share a 32GB Kingston USB doesn't exhibit the same sluggishness - It's quite noticeable with Big Sur and I'm curious to hear and to know about this phenomenon on similar iMacs from that year or in general.

To tally it all up.
We're talking the USB installation media made using the official Apple Support article way and on a USB 3 key using an USB 3 port.
We're also talking the Recovery side of things - I am somewhat aware that I probably have the Recovery Partition sitting on the internal HDD and not on my SSD, but what's the verdict here?

I am wanting to install Big Sur release version once again for the 3rd time and I have a desire to know about where my error lies, if any.

Thank you.

PS.. if I am to make a video of the installation - boot time and all (not actually installing Big Sur) please type that in a comment. It will be a horrendous recording taking using either my iPad or iPhone

PPS: I think that it's in order to recognize that I am fully aware that I am booting from and using a USB 3 media to start something that big as macOS Big Sur, but I also see past installation media - even from the same USB key of those I am in possession of react much better to opening windows and apps like the Terminal and Disk Utility for prepping a disk.
 
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