What do I need to upgrade for 4k gaming?

[haaammit]

Hi all. I feel like upgrading my system so I can get into 4k gaming. Current specs are:

MSI B450 MAX II m/b
Ryzen 5600X
Ballistix 16Gb Ram @3600MHz
Sapphire RX6600XT Nitro
EVGA Supernova 850w PSU

CPU currently cooled under custom loop - I want to add the new GPU to the loop. I assume the CPU/Mobo combi are fine, as is the PSU, but the GPU will need upgrading? Would it be worth upgrading the ram and if so add another 2 x 8gb for a total of 4 sticks or replace with 2 x 16gb?

Not sure of budget, so after an idea of cost as well. Many thanks!

 

[haaammit]

Thanks for the replies - I think I'll probably see if I can grab either a 6800 or a 6800xt for this system and see how we go.

Worth increasing the RAM or not? Ta

 

[haaammit]

Meant to say currently at 120hz 1080P - I like games like No Man's Sky, Subnautica, GTA, 7 Days that kind of thing when I get a chance to game!
As I say I think I'm going to go 6800/XT and try 1440P 144Hz as a jump up
Many thanks for the advice and replies, even you @tamzzy ...... x