Resolution issues on RX580

Hi guys,

I'm having resolutions problems with my Hackintosh. My build is:

i5 6500 MSI H270 RX580 Display Sony TV XE9005 4K Using HDMI 2.0

So, if I use 1080p, everything is ok till you get closer and notice that fonts are blurry, the image is not sharp. And if I scale to 4K everything is very small and not clear. Can you please help?

Thanks!