So I bought this monitor https://www.lg.com/ph/monitors/lg-20M39H-B. I used it using HDMI but my resolution is limited to 1366x768 only but according to the website, it support 1600x900 (in D-Sub). Can anyone explain what this is? Because I really want to used this in 900p resolution. Should I use VGA in order to get 900p?