you should not upgrade to the ultra 9 285k bc the 13900k outperforms in gaming especially in higher res

the ultra 9 285k is a good cpu with great multi thread performance but the 13900k has a better clock speed and better multicore performance

since this pc is for gaming the ultra 9 285k would lose to the 13900k. But in workstation tasks it beats the 13900k.

a better upgrade wouldve been the 7800x3d (better 3d V cache) or 14900k