4 vs 8 RAM sticks for EPYC Rome build?

[FaSti]

I'm putting together an AMD EPYC Rome based machine. The board I'm using ist ASRock's ROMED8-2T. I'm planing to run TrueNAS Scale (Debian based).
Does it matter weather I use 4 RAM sticks (32 GB, ECC, DDR4, dual rank, CL22) or 8 RAM sticks (16 GB, ECC, DDR4, single rank, CL22)?

 

[ari2asem]

go for 8 sticks for the best performance...

and 8 sticks of 32gb

 

[FaSti]

8 sticks of 32 would be best, but the budget is limited.... Going for 4 x 32 GB dual rank instead of 8 x 16 GB single rank would give the option to upgrade later. So if the 4 x 32 GB dual rank version would not come with any relevant shortcomings in performance, I would prefere that. What is the reason for 8 sticks single rank performing better and how big is the difference?

 

[ari2asem]

https://forums.servethehome.com/index.php?threads/amd-epyc-performance-impact-of-runing-4-channel-memory-instead-of-8-channels.21095/

https://www.servethehome.com/amd-epyc-7002-rome-cpus-with-half-memory-bandwidth/

https://forums.servethehome.com/index.php?threads/h11dsi-nt-and-octal-channel-memory.27297/

https://www.servethehome.com/amd-epyc-naples-memory-population-performance-impact-at-16-cores/

 

[mirrormax]

4x32 prob, then upgrade later if needed, unless your usecase is really gonna saturate 8channel bandwith.