New 2018 MacBook Pros-Downgrade to Sierra

[cosolin]

Looking to purchase a new, just announced, 2018 Macbook Pro, but am wondering about compatible OS. Comes preloaded with High Sierra, but given certain software we're still running, we would like to downgrade to Sierra OS.

We've done this on 2017 machines, just wondering if the new machines can accommodate Sierra as well.

Thanks for any information on this.

 

[Significant1]

No, older versions lack drivers for the new hardware.

 

[cosolin]

Thanks for your reply. Do you happen to know what drivers it lacks? The 2017 macbook pros could not be downgraded below Sierra because of the touch bar, but other than that, what drivers would it lack. I guess if all else fails, I could ask apple...

 

[BeatCrazy]

Thanks for your reply. Do you happen to know what drivers it lacks? The 2017 macbook pros could not be downgraded below Sierra because of the touch bar, but other than that, what drivers would it lack. I guess if all else fails, I could ask apple...

Zero chance regular Sierra will work. The 2018s have the T2 chip, which authenticates which OS is signed/compatible in order to boot.

 

[haruhiko]

You can't. Just test your software on High Sierra before buying.

 

[AuricBlue]

If you need to run at Sierra on the new MacBook Pro for a specific app you can always try using virtualization via VMware Fusion or Parallels Desktop. They should both be able to be at Sierra just fine. VirtualBox should even work, but I don’t think it has just drivers for macOS like Parallels or VMware.

 

[Significant1]

Thanks for your reply. Do you happen to know what drivers it lacks? The 2017 macbook pros could not be downgraded below Sierra because of the touch bar, but other than that, what drivers would it lack. I guess if all else fails, I could ask apple...

Mac's only support the macOS version they where introduced with and newer. It has always been that way. It's the price of bundling drivers with the OS, so users don"t have to mess with it like windows.

It is drivers for any new hardware (even the new processors might need tweaks to be fully supported) and entries in some lists telling the macOS which Mac's it support on installation time, that is missing.

 

[themp]

Zero chance regular Sierra will work. The 2018s have the T2 chip, which authenticates which OS is signed/compatible in order to boot.

Seriously, High Sierra barely works!

 

[maximit]

As a side note secure boot can be turned off.

 

[cosolin]

Thanks for all replies. So, looks likes I've got some software checking to do. Luckily, I've got a machine I generally use as a guinea pig for software testing.

 

[chrfr]

As a side note secure boot can be turned off.

Regardless, that won't enable the use of Sierra on these computers.