Windows 8 resolution scaling problem?

Hi there guys!

I am new to this forum, and I have a big problem upon getting my new 4k dell inspiron laptop. I thought it's going to be 4k resolution but when I check my resolution on whatismyscreenresolution.com it shows 1536x864. I wonder if it's a problem with my computer or windows 8? I've heard that there is some scaling problem with windows 8.

If anyone knows or have experienced the similar issue?

Thanks.