Help! No HDMI 60hz 4K output

[Kajetan_3]

Hi, my question is quite simple. Why can an integrated Intel HD graphics card run desktop applications in 4k 60Hz, while monitor is connected through a display port, bot not when using HDMI (hence 30Hz limit). I Recently bought a new 4K LG 27UD68 and I want to use it with my Lenovo Y50-70 laptop. It comes with i7 CPU, Intel HD integrated graphics and GTX 860M. I know it's not a 4k gaming config, but I don't intend to use it like that anyway. Just casual net-browsing and 4k video playback in particular.
So the main question is why DP can run 4k 60zh and HDMI can't and can i get the DP to HDMI switch and still benefit from DP capabilities? (because I don't have a DP port in the laptop I mentioned earlier)
Is simply buying a DP to HDMI adapter a plain and simple solution?
Any piece of advice will be appreciated and sorry for bad English.

 

[Barty1884]

The GPU (860M) is HDMI 1.4 (max 4K @ 30HZ)....whereas 4K @ 60Hz over HDMI required HDMI 2.0.

DP has been able to support 4K 60Hz+ for a few generations now.

Your monitor only takes HDMI 2.0 or DP 'in'. With only HDMI 1.4 available to you, your max is 4K @ 30Hz.

 

[Kajetan_3]

Thanks a lot.