I have tried multiple speedtest mostly to fiber connection and still only get at max 300 mbs.
How many channels on your cable modem up/down do you have - give us the make/model # of your cable modem, and we can find that out.
If you don't have the right number of channels, your speed will be limited to an upper amount. I had to upgrade my modem that way, since the modem I was using (an older model I had for a while) didn't have the right number of channels. When I upgraded to one with the proper number - speed increased.
Note: I have been with Cox broadband since the "Cox@Home" days and the big grey foot warmer modems (2000-01 time frame) - and also on the internet since 1993 - and prior to that on BBS's even longer back to 1987...
