I can't find any site or page that tells me the laptop HDMI port is 2.x. When I see this, it means the port is 1.x and will do as you found out.
Try 1080p output on that port. It's not as if the laptop can run games at 4K.
I have lenovo ideapad y700 17isk and I just bought LG 4K 27UD58 monitor ( http://www.lg.com/pa_en/monitors/lg-27UD58 ).
I connected the monitor to the laptop using HDMI 2.0 cable.(This 2.0 DHMI cabel should support 4K - 60hz )
I should get 3840x2160 resolution on 60hz but it is max 30hz.
Can you help me, what I need to do in order to get the LG working at 4k-60hz?
Thank you a lot.
This one tip will help you sleep better tonight
A few seconds are all you need to get a better night's rest.