Are you on build 1703 of Win 10? (right click start, choose run..., type
winver and press enter). The location of the power menu has changed in latest build.
I only ask as how are you getting to power? If I search for Change Advanced Power Options in cortana it loads Bing which isn't overly useful
You can however right click start button and choose Power Options - this opens the Power & Sleep settings menu now instead of taking you direct to the control panel window
to reach control panel, you have to choose Additional power settings off the settings page
I swapped my plan to High Performance and back again and PC lets me save them.
reason yours isn't could be Samsung as above or perhaps motherboard drivers/BIOS upgrade.
no, don't need Magician to use drive - its drive management, its not the program you use to backup contents -
http://www.samsung.com/semiconductor/minisite/ssd/product/consumer/magician.html