Synology only offers network card upgrades for certain NAS. I’ll show you how you can still enjoy a faster port using a USB LAN adapter.
Upgrade Your Synology NAS to 2.5 GbE
Synology DS1520+ - buy at digitec
2.5gbit and DSM 7 : r/synology
USB 2.5Gb Ethernet Adapter, ULT-WIIQ USB 3.0 to 2.5 Gigabit RJ45 LAN Network Adapter Cable, 10/100/1000/2500M Full Speed NIC for Mac OS, iOS, Windows, Linux, Dell XPS, Thinkpad X, Synology NAS
Teamwork: testing an APC UPS with Synology NAS - digitec
Upgrade del Synology NAS: 2,5 gigabit con adattatore LAN USB - digitec
Synology DS720+ - buy at digitec
Synology Outlook 2023: DiskStation Manager 7.2 and new hardware announced - Galaxus
Delock Adapter USB Typ-A Stecker zu 2,5 Gigabit LAN (USB 3.0, RJ45) - digitec
【2.5Gb USB 3.0 Lan Adapter】 The USB A 3.0 to RJ-45 adapter supports 10/100/1000/2500 Mbps via a USB A 3.0 port. 2.5Gbps is 2.5x faster than 1000Mbps
USB 2.5Gb Ethernet Adapter, ULT-WIIQ USB 3.0 to 2.5 Gigabit RJ45 LAN Network Adapter Cable, 10/100/1000/2500M Full Speed NIC for Mac OS, iOS, Windows
UL Listed PWR 12V 60W AC Adapter Compatible with Synology DiskStation DS218+ DS218j Ds216j DS216 II; WD My Cloud Pro PR2100 PR4100 EX2 NAS Power
Accessories
Digitus DN-3028 (USB, USB-C, RJ45) - buy at digitec