What memory does the Dell Vostro 15 3558 support?

Question

RAM

There is a laptop Dell Vostro 15 3558 i3 5005u
The original is DDR3L 1600 CL11 Micron
2 memory slots inside.
In some forums they write that a maximum of 8 gigs of memory, in others - 16 gigs.

according to S / N 20LJFC2, a datasheet breaks through, from which it follows:
https://dl.dell.com/topicspdf/vostro-15-3558-lapto...

Memory connector two internally accessible DDR3L connector
Memory capacity 2 GB, 4 GB, and 8 GB
Memory speed 1600 MHz
Minimum memory 2 GB
Maximum memory 16 GB

I bought 2 sticks similar to DDR3L 1600 CL11 from Kingston 1.35V
Model: PSD38G1600L2S
Squeak during installation, one for 8 gigs, that both for 8.

What could be the problem?
With micron 4 gigs it works fine.
Thank you.