Out-of-touch old gamer looking for 3090-compatible components - eviltoast

Title pretty much tells you all you need to know about my situation. In a turn of events tonight I’ve been gifted a used but working EVGA 3090 card to replace my seven year old 1070.

My current system hardware specs are:

CPU: AMD Ryzen 9 5900X 12-Core (upgraded from Ryzen 5 last year)

GPU: MSI 1070

MoBo: MSI MAG B550 TOMAHAWK

PSU - Corsair CX-550 550 Watt

x4 8GB Installed Memory

I also have a 2tb SSD drive with my OS and games installed, and 4 8tb HDD for media.

My main concern is with needing to replace my MoBo with a x3 PCi board and worries about my PSU not being powerful enough. I’m not particularly worried about my tower is a Phanteks Enthoo Pro PH-ES614PC_BK.

Thanks in advance!