Intel i9 10900k is a 125 watt TDP CPU, my opinion your case is quite squeezy for use with such hot chip.
I had a friend who also had i9 but his setup uses the Cooler Master H500P.
Much bigger and spacious case hardly can feel any heat from it
since the case uses 200mm fan.
My suggestion to you:
- If heat is your concern, downgrade to a 95 watt chip.
Like Intel i5 10500, for gaming there is no framerate penalty.
Only multi core task than will.
- Upgrade to a bigger case like Cooler master H500P, bigger fan,
bigger space so heat can dissipate better.
Try update BIOS as well if you have not done before.
Last update for BIOS is 2020/12/14:
https://www.gigabyte.com/sg/Motherboard/Z490-AORUS-ULTRA-rev-1x/support#support-dl-bios