I had the same issue with the 60d and gigabit internet with PPPOE. I
never found a good solution, so I decided to upgrade. After weighing my
options, sticking with an upgraded Fortigate seemed like the best bet
(as opposed to going with a PFSense box...
The Fortinet Security Fabric brings together the concepts of convergence and consolidation to provide comprehensive cybersecurity protection for all users, devices, and applications and across all network edges.