The Router Charts graphs below show the top end of the storage benchmark write and read charts using our standard procedure with USB 3.0 connections and NTFS drive format. I disabled the Reducing USB 3.0 interference setting in the 2.4 GHz Wireless Professional settings tab and also disabled iTunes, DLNA and FTP servers before running the tests.
The AC1900 class Linksys WRT1900ACS continues its hold on top place, with write throughput just shy of twice the 55 MB/s measured for the RT-AC88U. The gap between the Linksys and AC88U is smaller for read, with the ASUS measured at 88 MB/s and the Linksys at 106 MB/s. Note that NETGEAR's R8500 has elbowed its way into Linksys' dominance of the top of the read storage charts with 94 MB/s.
Storage Performance Comparison - USB 3.0 / NTFS
Routing throughput was measured using our standard router test process with the router loaded with 18.104.22.168.380_858 firmware. Table 3 summarizes the results and includes the NETGEAR R8500 for comparison, since it uses the same Broadcom processor. The AC88U's 802 Mbps downlink (WAN-LAN) throughput bests the NETGEAR's by 40 Mbps while uplink is 20 Mbps lower than the NETGEAR. The ASUS lags behind the NETGEAR around 140 Mbps for the simultaneous up and downlink test.
|Test Description||ASUS RT-AC88U||NETGEAR R8500|
|WAN-LAN (Mbps)||802||761 Mbps|
|LAN-WAN (Mbps)||791||809 Mbps|
|Total Simultaneous (Mbps)||1406||1546 Mbps|
|Maximum Simultaneous Connections||35,938||38,424|
Table 3: Comparative routing performance
For the unidirectional tests, the IxChariot chart below is typical of what we see with other current-generation routers. Up and downlink throughput is evenly matched.
ASUS RT-AC88U routing throughput unidirectional summary
The start of the simultaneous bidirectional test shows the usual IxChariot quirk. But once things settle down after 10 seconds in, uplink throughput gains the upper hand. It's not clear what causes the downlink throughput drop at the 45 second mark.
ASUS RT-AC88U routing throughput bidirectional summary
In all, the differences in routing throughput are relatively minor and shouldn't be the deciding factor in router selection.
The ASUS RT-AC88U was tested using our Version 8 Wireless test process with 22.214.171.124.380_858 firmware loaded. Our standard practice centers the router's antennas on the turntable, both front-to-back and side-to-side in the chamber. This method is intended to keep maximum distance between the router under test and chamber antennas as the router rotates during test. The photo below shows the AC88U in the test chamber.
ASUS RT-AC88U in test chamber
I've decided to stop showing the Benchmark summary because it doesn't really add anything to the analysis. Instead, let's compare average wireless throughput for similar routers. I filtered the charts to show the 2.4 and 5 GHz down and uplink profile benchmarks for all 4x4 router classes, i.e. AC2350, AC2600, AC3100 and AC5300.
2.4 GHz average throughput comparison - all 4x4 router classes
It's clear there is no correlation between higher class and higher average performance for either band.