The good news is you can replace the internal SSD. Read http://www.crucial.com/usa/en/compatible-upgrade-for/Lenovo/legion-y520-15ikbm to see the usual laptop size SSDs.
Since there is no bay for another drive, you have to swap in a bigger SSD.
In parting I have a work laptop with just 500GB SSD. Seems ample.
Hey guys, I got the Lenovo Legion Y520-15IKBM i5, 1060 3gb max-q, 8gb ram with only 256 gb ssd. And i basically don't have that much space left on my laptop. So I was wondering whether it's possible to add a new harddrive - doesn't matter if ssd or hdd, I just want at least another 256 gb, but 1tb would also be perfect.

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