1/2 of the problem here is the modem and 1/2 being your router.
The cgn3 currently has a bug where it doesn't alway link properly to 10/100 devices. Your router only has 10/100 ports, so it's being effected
(There was someone else on here with the exact same router with same issue)
If it was just installed yesterday, it may not be on the latest firmware, which helps some bridge mode stuff but not this.
Even if this bug did not exist, your max speed would be throttled via the router. You would never get over 100 with that unit.
You would be best to invest in a Good router with gigabit ports. (And even at that level of quality difference between a $70 gig port one and a $150+ one)
The cgn3 currently has a bug where it doesn't alway link properly to 10/100 devices. Your router only has 10/100 ports, so it's being effected
(There was someone else on here with the exact same router with same issue)
If it was just installed yesterday, it may not be on the latest firmware, which helps some bridge mode stuff but not this.
Even if this bug did not exist, your max speed would be throttled via the router. You would never get over 100 with that unit.
You would be best to invest in a Good router with gigabit ports. (And even at that level of quality difference between a $70 gig port one and a $150+ one)