Adding more ram to laptop?

I have a question. I've bought myself a lenovo y50-70 laptop and i've got spare 4 gb of ram, is it alright if i add them to my new pc, ? Would it increace the performance, or dicrease. I have no problem with the performance of my new laptop, but i'm just wondering what would happen.

How much RAM is in it? I've checked online and seen varies results.

You RAM slots might already be full. Also you need to make sure the RAM is compatible. Increasing your RAM will not decrease performance. But if you already have 16 GB you will probably not notice unless you are using a lot of memory. It will at least decrease the need of virtually memory which is a nice boost.

You really don't need more ram dude, but 4 gb couldn't be added, if you really wanted 32 gb get 2 16 gb sticks.

It won't affect because most of the time, you only use less than 8gb ram which make the other ram at idle status.