Oh I forgot to mention - the Chelsio NIC with a Wiitek SFP+ to RJ45 Copper Module (10GBase-T) and it works fine at 2.5Gbps. I have my Chelsio port 1 connected (using the Wiitek) direct to an MB8611 Xfinity modem and it links up at 2.5Gbps. I'm getting roughtly 1.2Gbps (overprovisioned) on download.