Looking to Purchase New iMacs

[petedogg]

Like the title says, looking to purchase new iMacs for a lab. Currently we are running 10.9 Mavericks image we built and deploy with Casper Imaging. Since we are seeing problems with Yosemite, we are hesitant to update and would like to re-image the machines we purchase with the 10.9 image we currently use. What issues will I run into downgrading from 10.10 to 10.9?

[barnesaw]

In all likelihood, Macs that won't boot and are non-functional.

[davidacland · Accepted solution]

Unless its the new 5k iMacs, the rest of the range are still mid-2014 or earlier so should run 10.9 ok.

For lab purposes we have just started deploying 10.10 in small numbers. In our opinion, we're going to be forced onto 10.10 soon enough so we might as well get ahead of it. Going straight to 10.10 will also mean you don't create another upgrade task for yourself later on.

We've been installing FCP X, Logic X, Office 2011, joining to AD, mapping network drives, using large MFPs etc and are everything is working ok for us.

[Rayfield]

As a good rule of thumb, is the Mac OS was released after the machine was released then it should be good.

The latest 21.5 inch iMacs were released on June 14th.
10.9.5 was released on September 17th

For reference: http://en.wikipedia.org/wiki/IMac_%28Intel-based%29#Slim_Unibody_iMac
http://en.wikipedia.org/wiki/OS_X_Mavericks

[acdesigntech]

Why guess? Download and run MacTracker. GREAT app!!!! It will tell you the original OS a mac came with and what it will accept for an OS install, plus what the onboard chipsets are/were for video, processor, RAM, etc.

Per MT: Apple is still selling the 14,2 (27") and 14,4 (21.5") model identifier iMacs, which both can be rolled back to 10.9.5.

And @davidacland is right. Only the 5k iMacs require 10.10 minimum right now. That will change soon, so buy em while you can.

[RobertHammen]

http://support.apple.com/en-us/ht1159 comes in handy for knowing which builds ship with which computers.

Apple does not officially support a method to downgrade OS X, even if a machine is capable of running 10.9.x, but if it shipped to you with 10.10.x. Doesn't mean it can't be done, they just won't tell you how to do it, or support any weird issues that may arise (sometimes there are EFI and SMC firmware updates with specific minimum OSes).

[acdesigntech]

Mactracker will tell you what OS a model originally shipped with, then what OS it later shipped with. In the case of the 14,2 imac, its still shipping with 10.9.4 - just set one up today.

[petedogg]

Thanks guys, they shipped with Yosemite, so I just erased the drive and ran our 10.9.2 image. Seems to be working fine.