1.Different LED allocation on Fast Ethernet ports.
V1: 2 LEDs for Fast Ethernet ports.
V2: 1 LED for Fast Ethernet ports.
2.Check the serial number from FCC label that located on bottom of FGSW-2620CS.
3.Login Web interface; if your FGSW-2620CS is hardware version 2, it will displays Hardware Version v2.0 in “System > System Information”.