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Wireless Reviews

Introduction

This router was one of the first retested with our new wireless test process. So the retest, using 3.0.0.4.354 firmware, was done using 5 dB steps vs. the 3 dB we subsequently changed to.

Since the AC66U is the top-ranked AC1750 class router, it is frequently compared to other products. And it has always bugged me that the comparison plots like the one below didn't provide equivalent detail for the ASUS' performance.

Typical ASUS RT-AC66U performance comparison

Typical ASUS RT-AC66U performance comparison

I also wondered whether the first test results were a fluke because the AC66U so consistently outperformed all other AC1750 routers. So awhile ago, I reran the test using 3.0.0.4.354 firmware, but using 3dB steps that are now our standard. Other things got in the way, however, and I did not post the new results in the Router Charts.

Note that since I had determined in the first test that the "0 degree" position in the test chamber (with the rear of the router closest to the test chamber antennas) provided best performance, I ran both retests in that position only.

When NETGEAR briefed me on its suit against ASUS, they noted that ASUS had posted new firmware for the two routers named in the suit (the RT-AC66U and RT-N65U) after NETGEAR had notified ASUS of its intent to sue.

NETGEAR said their tests showed the new firmware reduced transmit power levels. So I decided to retest the AC66U once more, this time with the latest 3.0.0.4.372_1300-gd292488 version (screenshot below).

Typical ASUS RT-AC66U performance comparison

Typical ASUS RT-AC66U performance comparison

Benchmark Summary

The benchmark summary for the second retest compared to the original below it, shows slight reductions in average throughput for both 2.4 and 5 GHz unidirectional tests.

ASUS RT-AC66U Second Retest Benchmark Summary

ASUS RT-AC66U Second Retest Benchmark Summary

However, simultaneous up/down throughput on both bands increased, from 165 to 172 Mbps in 2.4 GHz and 484 to 524 Mbps in 5 GHz.

ASUS RT-AC66U First Retest Benchmark Summary

ASUS RT-AC66U First Retest Benchmark Summary

2.4 GHz Throughput vs. Attenuation

Looking at the throughput vs. attenuation plots more clearly shows the differences, as well as similarities. In the 2.4 GHz downlink plot below, all three test runs show an initial throughput dip with attenuation in the teens. The plots converge with attenuation from 20 to 30 dB, then clearly diverge starting at around 33 dB of attenuation. The three test runs then maintain their relative positions all the way down to the maximum 63 dB of attenuation the test gear can provide. The initial 5 dB step 3.354 run comes in highest, the 3 dB step 3.354 retest in the middle and the new 4.372 firmware the lowest.

ASUS RT-AC66U 2.4 GHz Downlink Throughput vs. Attenuation

ASUS RT-AC66U 2.4 GHz Downlink Throughput vs. Attenuation

Differences in 2.4 GHz uplink performance are much harder to parse. In fact, I can't really say that there is any significant difference

ASUS RT-AC66U 2.4 GHz Uplink Throughput vs. Attenuation

ASUS RT-AC66U 2.4 GHz Uplink Throughput vs. Attenuation

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