Short version: Something about the combination of the Intel i5-1035G1 chip, the integrated Intel UHD graphics and something about the HDMI port does not work to get 4K output to an external monitor. Details below and links at the bottom.
Long version:
I have a 4 year old Acer Aspire and a really low-end Asus Chromebook which both connect to my external 4K monitor (a TCL Roku TV) just fine. At 4K resolution. Looks great.
I bought a new PC. Windows 10. Intel i5-1035G1. Beautiful spec. Intel UHD graphics card.
IT WILL NOT CONNECT AT 4K TO MY EXTERNAL MONITOR! It drove me nuts. I connect it, it shows at 1080p (1920x1080) and offers no higher options.
The Intel UHD card is rated for at least 4K. And I'm sure my TV can do it because I have used it as an external monitor with other computers at 4K with literally no fiddling or problems at all.
I called Dell and after a very long time, during which they remote-controlled my computer (which I hate), and downloaded a bunch of new drivers, etc., he finally found deep in the documentation that the HDMI hardware does not support 4K. How can that even be, as all my research shows that even really old HDMI technology can support 4k (maybe not at 60hz, but it can push the resolution).
After that, I discovered other information that none of the Dell xx93 computers (Dell Inspiron 5593, for example) can push 4K.
How can they even make a computer like that? My old computer and my old+cheap computer both support it.
At least I can say that Dell gave me a full refund.
Moving on. I found another computer I liked. Gateway from Walmart. Also Intel i5-1035G1, also Intel UHD graphics processor.
Same problem!!
It's not the monitor/TV. It's not the cable. I simply took the cable out of my old computer, plugged it into the new computer. Didn't work, in either of the 2 new computers.
I even took the Gateway to BestBuy where the guy very graciously let me plug in my computer (first with my cable, then with their cable) to a 4K television on the floor. Same problem.
So I know it's not the cable and I know it's not the 4K tv being used as a monitor.
It is for sure something fishy about the chip and/or the integrated graphics and/or the HDMI port.
But why?!! So frustrating. And how do I avoid buying another computer where this doesn't work?
All I know is at this point, because this is a deal-breaker item for me, the next computer I buy will have to be in person and the salesperson will have to show me before I buy that it connects in 4K.
The only information I have found that acknowledges this problem:
Deep in the responses/comments: https://www.dell.com/community/Inspiron/Dell-Inspiron-5593-Native-resolution-on-external-monitor-Dell/td-p/7419597
Page 12 of this user guide https://topics-cdn.dell.com/pdf/inspiron-15-5593-laptop_setup-guide_en-us.pdf
https://www.intel.com/content/www/us/en/support/articles/000023781/graphics.html