From what I understand, you need to switch the position of the drives...
The SSD needs to be in the original position of the drive that shipped, and using the original sata cable.
Move the HDD to the secondary spot and use the new cable that came with the kit.
From what I've read, this is the only way to use the SSD as the boot drive.
I'm getting ready to do the exact thing to my new mini with a Samsung 840 pro...
No it doesn't. If you watch the OWC install guide available on their site or youtube the ssd is in the bottom slot and connected to the secondary connector.
The “Fusion Drive” option for the 2012 Mac minis can cause some severe data loss if you’re not careful. It’s a bit of a “perfect storm,” but it’s worth noting if you’re adding an SSD as a second drive in your Mac mini.
This particular instance affects you only if:
You are upgrading a 2012 Mac mini.
That 2012 Mac mini shipped with Mac OS X 10.8.2
You are adding an SSD to this Mac mini as a second drive, alongside the existing Hard Drive using an OWC Data Doubler Kit.
If your installation involves all three factors, then you need to pay attention, as your installation will be affected. If one or more of these factors are not involved, then you don’t have to worry, you can proceed as normal.
If you are one of the affected Mac mini owners, then installing an SSD is a little different. The preferred method is the “Internet Restore” method. Perform the following steps in order to format your SSD and transfer your OS and data from your original drive.
Make sure your data is backed up, just to be safe.
Install your SSD in your Mac mini, following the instructions.
Restart your computer and boot to the internal hard drive like normal.
You will likely get a dialog box stating that a drive is “unreadable.” Click the “Initialize” button to open Disk Utility. If you don’t get this warning, you can find Disk Utility at Applications/Utilities/Disk Utility.app
Select the SSD from the list on the left side of the Disk Utility window and Click on the Partition tab.
Select “1 partition” for the Volume Scheme, set the format to “Mac OS Extended (Journaled)” and give the drive a name. You can then click the “Apply” button to format the drive.
Once the drive is formatted and shows in the Finder, you can then shut down.
Make sure you’re connected to a network. While it’s preferable that you connect via Ethernet, you can connect via AirPort; it will just be slower.
Restart to the OS X Recovery Partition by holding down Command-R until you get the Recovery Partition’s main window. It is very important to note that you should not use the version of Disk Utility in the Recovery Partition; it will see the two separate drives as a “damaged” Fusion drive and try to repair it; allowing it to do so will destroy your data.
Select the option to “Reinstall OS X” choosing the SSD to install the OS on. If you’re connecting via AirPort, you may be prompted to connect to your wireless network.
Follow the prompts to install.The actual downloading and installation process may take a while.
After the OS is installed, follow the prompts to set up your computer. When asked, choose the option to import your data from another drive and select your original drive as the source.
Once the migration is complete, your computer should boot to your SSD.
You can use the Disk Utility like you did before and format your original hard drive as desired.
You will now be able to use your Mac mini normally.
While the above method is the preferred way to do this, if you do not have an Internet connection, you won’t be able to reinstall your OS this way. In this instance, you will need to use the “External” method.
Install your SSD in an external enclosure (USB or FireWire) and connect it to your Mac mini.
Boot to your Hard Drive.
You will likely get a dialog box stating that a drive is “unreadable.” Click the “Initialize” button to open Disk Utility. If you don’t get this warning, you can find Disk Utility at Applications/Utilities/Disk Utility.app
Select the SSD from the list on the left side of the Disk Utility window and Click on the Partition tab.
Select “1 partition” for the Volume Scheme, set the format to “Mac OS Extended (Journaled)” and give the drive a name. You can then click the “Apply” button to format the drive.
Once the drive is formatted and shows in the Finder, you can then shut down.
Restart to the OS X Recovery Partition by holding down Command-R until you get the Recovery Partition’s main window.
Enter Disk Utility – since the SSD is in an external enclosure, you don’t need to worry about Disk Utility trying to create a Fusion drive.
Click on the SSD in the list on the left and select the Restore tab. Drag the original drive’s icon from the left onto the “Source” field. Do the same with the SSD into the “Destination” field.
Click the Restore button to copy all your data over to the SSD, then shut down.
Restart holding down the Option key. Select the SSD/External drive as your boot drive and continue.
Use the Disk Utility in Applications/Utilites to format your hard drive as desired.
Shutdown, remove your SSD from the external enclosure, and install it in your mini.
Once the SSD is installed, you should restart the mini and login. Go to to the Startup Disk preference pane and select your SSD as your boot drive.
You can now use your Mac mini normally.
No matter which method you use, once you have both an SSD and a platter-based drive installed in your Mac mini, you should not use the Disk Utility in your Recovery Partition on those drives; it will see those drives as a “broken” Fusion array and try to repair it, destroying your data in the process.
