The iMac14,2 is a stable SysDef just like the MacPro3,1. I've been using the 14,2 SysDef since El Capitan on all my Haswell & Skylake systems in preparation for Sierra. The iMac14,2 works very well for those systems with a discrete graphics card, while iMac14,1 works with on-board graphics.
You will not be able to install Sierra with the MacPro3,1 since Apple no longer supports the 2008 Mac Pro (3,1) in Sierra. So, you'll need to set up your current system with the iMac14,2 SysDef before you install Sierra.
You can use MultiBeast to change to the iMac14,2 SysDef by running MultiBeast and just selecting Customize > System Definitions > iMac > iMac14,2.
However, I just noticed you haven't defined your system in either your Profile or in your signature block per the Forum Rules and Policies. By doing so, you can help us help you better.
Everything (except for sleep) has been working perfectly. But I just noticed that every time I reboot my machine it creates a new boot entry in the BIOS. Right now it's up to 41 boot entries.
Each entry is the same as in the attached pic - [UEFI: Samsung SSD 850 EVO 500GB, Partition 1] - but the second to last entry is always [UEFI OS (P5: Samsung SSD 850 EVO 500GB)] and the last entry is always [P5: Samsung SSD 850 EVO 500GB ]... not sure if any of that makes a difference. OS X 10.11.6 is the only OS installed and I only have 1 internal drive (Samsung 500GB SSD).
Any idea how I can safely remove the unnecessary entries and prevent this from happening in the future? Thanks!
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