I too am building a PC for second life use and here is what I am using:
Motherboard - Asus TUF Gaming x570 Pro
Processor - AMD Ryzen 5 5600x
Ram - Kingston HyperX Fury Renegade 3200MHZ DDR4 CL 15 DIMM (2- 8GB Stix to give me 16GB total)
Graphics Card - Nvidia GeForce RTX 3060 Ti
Monitor - Asus TUF Gaming VG259Q 24.5" 1080p 240 HZ
Not sure if this helps but hopefully this set up will run Second life smoother than my current set up.