I ran some network speed tests after the u-verse upgrade.
After connecting my iMac via wifi to our new wifi router downstairs, I get 200+ Mbps down AND up. For wifi, that’s really pretty good. I got over 600 MBps when my windows laptop was directly plugged into the new AT&T router gigabit ethernet port. Our ethernet over power line transceivers are apparently limiting the flow of traffic between floors to only 50 Mbps, so I’ll need to run some wires.
Also interesting, when I set the AT&T router 2.4 GHz and 5 GHz radios to the same SSID, my iMac connected to the lower, slower frequency range. I ended up setting them to different SSIDs, and picked the 5 GHz id to get the higher speed. So far, no video lag at all. What it does do is let you see which wifi devices see both frequencies, and which are 2.4 GHz only.