I went with Ketho's answer, but for those want to try something else, registry hacking has worked for some. Many thanks to
joshindaphils who posted the answer here; I've simply copy-pasted his answer below.
For whatever reason nVidia cripples shadowplay on laptops and does not allow the recording of your desktop.
To enable this feature copy the below text and use it to create a text file, name it what you wish, though with a .reg extension. Save it double click on it, afirm all popups, and bam you can now record your desktop:
Windows Registry Editor Version 5.00
Alternatively if you are familiar with regedit just add / edit these values.