The R6400 was tested using our V8 Wireless test process with V184.108.40.206_1.0.13 firmware. The Benchmark Summary below shows the average of throughput measurements made in all test locations.
NETGEAR R6300v2 Benchmark Summary
The 2.4 GHz downlink plot show a relatively tight performance range. The TP-LINK and ASUS have slightly higher throughput up to the 33 dB test, after which the TP-LINK continues to run slightly above the pack, while the ASUS drops to the bottom. The R6400 is at the bottom of the group out to 39 dB and then moves above the ASUS. In all, the plots indicate pretty similar performance.
2.4 GHz Downlink and Uplink Throughput vs Attenuation for AC1750 Class routers
The performance spread is wider for 2.4 GHz uplink, with the ASUS clearly above the other products for most of the tested range and the original R6300 clearly below. The R6400 and TP-LINK track very closely for most of plot.
The 5 GHz downlink benchmark shows the Archer C8 running above the other products throughout the tested range and disconnecting last. The R6400 starts out equal to the TP-LINK, but falls off faster to drop below the other three from 21 dB onward. 5 GHz uplink shows similar patterns for both R6400 and TP-LINK Archer C8.
5 GHz Downlink and Uplink Throughput vs Attenuation comparison
The Router Ranker placed the R6400 at #3 among AC1750 class routers tested with the current Version 8 test process. Ranking details are shown in the Performance Summary alongside the top-ranked TP-LINK Archer C8. The R6400's only #1 sub-rank is Maximum simultaneous connections, which contributes only 5% to the total ranking score. The worst sub-rank, 5 GHz range, is unfortunate, since that's of more interest to most AC class wireless router buyers.
Performance summary comparison
I suspect the R6400 with its separated-at-birth-from-the-R7000-Nighthawk styling—the external antennas in particular—may prompt more shoppers to give it a second look vs. the R6300's inside antenna format. They might even choose it over the R7000 and save $50 in the process. But the TP-LINK Archer C8 is a much better buy and performer, at currently around $120, and remains our top-ranked AC1750 class router.