I used an laptop equipped with a 2.5GHz Intel Core i5-3210M CPU, 4GB of memory, and an integrated Intel Centrino Ultimate-N 6300 Wi-Fi adapter to run my benchmark tests. The Ultimate-N 6300 can send and receive three simultaneous 150-mbps spatial streams (450 mbps in total); most adapters are limited to handling two (300 mbps in total). This was all the streaming I needed to evaluate the RT-AC66U's 802.11n performance (on both the 2.4- and 5GHz frequency bands). To measure the router's 802.11ac performance on the 5GHz frequency band, I configured a second RT-AC66U as a media bridge and connected that to the AVADirect's ethernet port.

To test the router, I positioned the client successively at five spots inside and outside a 2800-square-foot, ranch-style home (distances from the router are noted in each chart below). I used the open-source IPERF benchmark (and the JPERF Java graphical front end designed for it). To measure the router's downlink TCP throughput, I set up the laptop as a server and used a desktop PC hard-wired to the router as the client.

At close range, with the client 9 feet away from the router and in the same room, the RT-AC66U was more than twice as fast as the reference 802.11n router, delivering TCP throughput of 466 mbps. This was the second-highest performance of the five 802.11ac routers I tested at this location (the was slightly faster).

I was surprised to discover that the RT-AC66U performed even better when I moved the client into the kitchen, 20 feet away from the router with one wall in between. I suspect that the media bridge was being oversaturated at the closer proximity, though the orientation of the media bridge is another variable. In the bedroom, the bridge faced the router: In the kitchen, it was perpendicular to the router. Whatever the cause, the RT-AC66U's TCP throughput jumped to a staggering 525 mbps at this location--the fastest performance in the field by a wide margin.

The next two benchmark runs took place inside my home theater. This is a room-within-a-room design, with four walls of 2-by-4 framing and drywall inside four walls of 2-by-6 framing and drywall, with about 6 inches of dead air and fiberglass insulation separating them. My intent was to optimize the room's acoustics, not to build a Faraday cage, but many lesser routers and other wireless devices have had trouble penetrating it. However, none of the 802.11ac routers I tested had any difficulty reaching the client in this room, and three of them--including the RT-AC66U--sustained TCP throughput at more than twice the rate of the reference 802.11n router. As you can see from the chart below, the Asus was the fastest of them all, at 192 mpbs.