Took me six hours to resolve the problem you had
@JohnHa...
...and setup up similarities are striking. I have SONNET TEMPO SATA PRO PLUS with 2 boot volumes on it (this HAS to be removed until you 'normalise' the boot from your SSUBX (e.g. Shutdown and/or RESTART at least twice from SSUBX).
I have SSUAX 1TB --- basically the only two AHCI-based PCIe SSDs, with native TRIM support (no FW upgrade required, will boot reliably back to OS X9, both based on Samsung XP941 and SM951 respectively).
I got tripped up badly (time-wise) because I forgot about the impact of PRAM and SMC resets (PRAM mainly). It doesn't just "clear" errant [boot args] -- it also clears your NVIDIA BOOT ARGS GPU SETTINGS and SIP DISABLE and PERFORMANCE MODE and DISPLAY SETTINGS (basically ANYTHING and EVERYTHING you previously set up in the boot-args NVRAM variable)..
Had to strip it all back to SATA bay SSD and GT-120.. then start cloning from one of my personal Golden Master OS X builds - to the SSUAX/SSUBX (NOTE:
!no recovery volume possible!), then boot to PCIe AHCI and formally ANOINT your SSUBX as the **primary boot vol in System Preferences**
I wrote a lot of notes on getting back to a very advanced, super reliable multi-boot volume setup. I've included them below as a quick reference and/or in case they might help:
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Mac Startup Key Combinations **ON SYSTEM BOOT**
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(1) START UP FROM THE BUILT-IN MACOS RECOVERY SYSTEM / RECOVERY MODE: HOLD DOWN [ Command (⌘)-R ]
-- OR use ***Option-Command-R or Shift-Option-Command-R*** to start up from macOS Recovery over the Internet.
-- macOS Recovery installs different versions of macOS, depending on the key combination you use while starting up.
(2) Start up in SINGLE-USER MODE: HOLD DOWN [ Command-S ]
-- OR TYPE >> [sudo nvram boot-args="-s"]
-- This command will boot the system into Single User mode without needing to hold Command-S at startup.
**Disabled in macOS Mojave or later, or when using a firmware password.
(3) Reset NVRAM or PRAM: HOLD DOWN [ Option-Command-P-R ]
-- If your Mac is using a firmware password, it ignores this key combination or starts up from macOS Recovery.
CHECK 'NVRAM' STATUS before you reboot by opening Terminal - then TYPE >> [nvram boot-args]
-- This command displays the boot-args NVRAM variable.
-- If you reset NVRAM, this setting is cleared.
To DISABLE these features and have the system boot normally without any extra options, you can erase them from the nvram by either resetting it or, more specifically, by running either of the following commands in the Terminal (these will reset the boot arguments INSTEAD of resetting ALL the nvram variables):
TYPE >> [sudo nvram boot-args=""]
TYPE >> [sudo nvram -d boot-args]
OTHER METHODS..
TO start up in Target Disk Mode.. HOLD DOWN [ T ]
TO start up with the Apple Diagnostics utility.. HOLD DOWN [ D ]
TO start up in Safe Mode.. HOLD DOWN [ Shift (⇧) ]
TO start up in Verbose Mode.. HOLD DOWN [ Command-V ]
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NOTE: PERFORMANCE MODE on OS X EL CAPITAN 10.11 and LATER
-- To turn on PERFORMANCE MODE in OS X El Capitan 10.11 and later, use the nvram command to adjust the boot-args NVRAM variable.
-- If you see serverperfmode=1, performance mode is already turned on.
How to MANUALLY reset NVRAM: Shut down your Mac, then turn it on and immediately press and hold these four keys together: Option, Command, P and R. You can release the keys after about 20 seconds, during which your Mac might appear to restart.
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---- INSTRUCTIONS FOR DISABLING SIP IN TERMINAL ----
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Assuming that you know what you're doing, here is how to turn off System Integrity Protection on your Mac.
Turn off your Mac (Apple > Shut Down).
Hold down Command-R and press the Power button. Keep holding Command-R until the Apple logo appears.
Wait for OS X to boot into the OS X Utilities window.
Choose Utilities > Terminal.
TYPE >> sudo csrutil disable ..then PRESS the <enter> key
- Your Mac will automatically reboot and start up with SIP disabled.
- You can check the status of SIP by opening Terminal and entering [csrutil status].
- You should see "System Integrity Protection status: disabled."
---- INSTRUCTIONS TO 'ENABLE' (RESTORE) SIP IN TERMINAL ----
I always keep SIP off, but you can turn it on after kext installation by using the following command in recovery partition.
TYPE >> [ csrutil enable --without kext ]
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SUDO COMMANDS FOR EXECUTING 'TRIMFORCE ENABLE'
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CMD:: [ sudo trimforce enable <enter> ]
>>>>> TERMINAL PROCESSING NOTES == on execution (password).. ACTION confirmation.. 4-5 mins before auto-reboot
FINAL NOTE: in the terminal window, on execution - ENTER password.. wait for ACTION confirmation.. ALLOW 4-5 mins before auto-reboot (I have to share this because the temptation is to interrupt/reset your MAC because terminal gives little feedback whilst it is making the changes).
