HP EliteDesk 800 G1 DM (Mini) 4K

Greeting fellow Hackintosh-er's

I recently got my hands on a HP EliteDesk 800 G1 mini, a very tiny PC, for like 10,000 rupees, it has i5 4690T 8GB DDR3 RAM and a 250GB SSD. I already have a Windows machine (Aorus z390 mini itx + i5 9600k) and also already have Linux machine (HP ProDesk 600 G2 mini with pentium CPU) so I thought I would experiment with Hackintosh on the 800 G1.

I know the above model is old so may be 4K support is not possible but just wanted to ask if there is a chance to get it working, the CPU specs lists that 4K is supported on the Display port.

I have an LG 27 UL500, 4K UHD monitor that I would like to use with this machine. everything works fine with the latest version of Big Sur 11.3.1 and has been stable for a few weeks. the only thing that doesn't work is

1. Display Resolution is only 1080P with no option to increase it - I would like this to be 4K if possible.
   

Display Settings

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https://preview.redd.it/3kvid98z51271.png?width=587&format=png&auto=webp&s=7ede4ad6da60b1fb267acbd0c62034fae6480b05

Any help would be appreciated.