Can I replace RAM / SSD in G7 7790 without voiding warranty?

Also the second part: I remember that when I bought my inspiron 5000 series it had a sticker over screw hole, but that one has been put by the shop that sold me that model.

This confuses me a little because it looks like removing that sticker would void a shop warranty while afaik disk in that model was considered a "replacable element" and therefore according to Dell this should not void it.