My Samsung 860 EVO SSD running through an unbranded SATA to USB-C case read at around 400 MB/s and wrote at about 390 MB/s. Whilst I was about it, I used my disk benchmarking app Stibium to see how big a performance hit USB-A is against USB-C. You wouldn’t want to leave your external SSD connected to a USB-A port any longer than you have to, though. Whether this works through a dock to a USB-C/TB4 port on an M1 MacBook Air or Pro, I’m afraid I don’t know. In those cases, connect them instead to one of the USB-A ports on your M1 Mac mini. Some of those will work properly when connected to a USB-C/TB4 port, but many will fail to complete the Big Sur installation. But most external SSDs use cheaper SATA and USB-C interfaces. If the disk has a Thunderbolt interface, then you should be able to get it to work reliably using a certified Thunderbolt 3 cable to one of the USB-C/TB4 ports on your M1.
I know, why would anyone want to connect a USB-C disk to a USB-C port, you wonder.Ĭreating an external bootable disk for an M1 Mac still involves trial and error, though. The secret is to avoid connecting the disk to your M1 Mac’s USB-C port.
#Macos big sur 11.2 3 install#
Thanks to various users who’ve tried this, I can now reproducibly install a bootable copy of Big Sur 11.2 on a USB-C SSD which had previously refused to complete macOS installation. Before we get to the bad news, I thought I should share the good: it is possible to turn the majority of external SSDs into bootable disks for M1 Macs.