To replace stock Vodafone Gigabox modem/router with a new device you need to make sure that your new device uses same settings as the original router. Vodafone enforces PPPoE protocol for encapsulating frames, enther the following details on your new router:
Username: vodafone@vodafone.ie
Password: broadband
The above works fine on ASUS RT-AX88U router and works fine.
For Netgear devices you might have to set VLAN to 10 on the WAN interface.
dartron 