dell s3221qs refresh rate/resolution - help

[coco]

hi, i just got this dell s3221qs 4k/60hz. and need help from experience user.

trying to hook up to macbook pro2016 (run bootcamp win10- with graphic card intel irish 540) via hdmi cable (from dell ) and using adapter insigna (support 4k/60hz), however I am not getting a full screen stretch edge to edge, and resolution only 2k/30hz. did try to change some setting from OSD monitor , unfortunately did not get any result. have downloaded driver from dell and installed for this particular model monitor , still the same thing .
when plug in to ipad pro - getting only 2k/60hz.

how can i get 4k/60hz and full screen fit display stretch edge to edge
in the meantime i have ordered usb-c to display port whic will arrive next week and will try this .

would appreciate your help. thank you kindly

[coco]

update: managed to get it full screen mode by adjusting from intel graph control panel. but resolution can only recognize 2k/30hz.
when tried to boot-up to mac-os mojave , resolution still 2k/60hz. but only shown wallpaper on the screen.
have tried to go system preference - display - didn't find any setting/drop down menu that can enable to set 4k/60hz.
didn't have any success to get 4k/60hz. is it because macbook pro 2016 limitation
Thank you for your time and respond.