I have a SEi8 i5-8259U+16G/512GB. The description page says the HDMI ports can do 4K@60HZ but I can only get 30HZ so it seems they're only HDMI 1.4?
Anyway, I tried instead to use the USB-C port with a USBC->HDMI cable but it doesn't output video. I tested the cable on another computer and it works so I know the cable is fine. Is there an option in the BIOS somewhere to enable it?
Well the only resolution that I could find is go to Intel Iris Control Panel App and change display resolution to 2560x1440. Then you can change refresh rate to 60p Hz. Hope that help.