From the wiki:
Prerequisites
Before installing OpenMediaVault make sure your hardware is supported.
Minimum Requirements
CPU: Any i486 or amd64 compatible processor.
RAM: 1 GiB capacity
HDD:
System Drive: min. 4 GiB capacity
Data Drive: capacity according to your needs
I wonder where tu put my money on: RAM vs CPU vs ?
Core numbers ??
A12-9800: Compute Cores 12 (4 CPU + 8 GPU) 3.1GHz/3.8GHz L2 2048 TDP125W GPU R7 AM4 overkill 120 EUR --> MB Asus PRIME B350-PLUS ( 6 Sata rev 3.0, 4 USB 3.1 Gen1, 1 port M.2 , HDMI, DVI et VGA ) 100 EUR
A6-9500: Compute Cores 6 (2 CPU + 4 GPU) 3GHz/3.4GHz L2 1024 TDP65W GPU R5 AM4 not so bad 50 EUR --> MB Asus PRIME B350-PLUS ( 6 Sata rev 3.0, 4 USB 3.1 Gen1, 1 port M.2 , HDMI, DVI et VGA ) 100 EUR
AMD FX-8300 core 8 threads 8 3.3GHz/4.2GHz L2 8096 TDP95W AM3+ 100 EUR --> MB Asus M5A97 AMD 970/SB950 lan Realtek 8111F 100 EUR
Ram: 4Go, 8GO, 16GO usually crucial or kingstone non-ECC
HDD already bought: 6 * Seagate IronWolf 8 TB, ST8000VN0022
OS will be on a Kingston Technology - DTSE9G2/32GB USB 3.0