CPU + MOBO advice for a debian + Nextcloud NAS

[xetyr]

Well well well...

After many considerations, I'll probably opt for the following configuration :
• CPU Ryzen 5 PRO 5650G                                                                                    /150€
• MB ASRock B550M Pro4* (support ECC avec Cezanne, donc 5650G)                        /120€
• CPU fan be quiet! Pure Rock LP (45mm hauteur, <70mm du boitier)                       /55€
• Jonsbo N4 (SO CUUUUUTE)                                                                               /120€
• PSU be quiet! SFX Power 3 300W 80+ Bronze**                                                  /65€ 
• case fan PWM be quiet! Pure Wings 3 120mm PWM                                             /15€
• SSD (OS) Samsung 980 M.2 PCIe NVMe 250Go****                                           /60€ 
• RAM Lenovo ThinkSystem 16 Go TruDDR4 3200 MHz ECC***                              /200€ 

TOTAL COST W/ STORAGE :                                                                               785€


To be honnest, I hoped to create a setup with the Ryzen 5 Pro 3400G, aiming a "low power config". In the end it seems difficult to find a MB supporting ECC for this model.
MB constructors are guarantying ECC support only for PRO series, and the 5650G Pro with the B550M Pro4 from ASRock are ECC compliant, according to the official doc. So it should be the most reasonable choice.
Have you any last advice considering this update ?