I used the open air test method described here to test the Extreme's wireless performance. Testing was done using our standard wireless test client, an Intel Wi-Fi Link 5300 AGN mini-PCIe card in a Dell Mini 12 running WinXP Home SP3. Since Intel continues to update the 5300's drivers, I periodically check for updates and found one. So I upgraded the driver to XP version 126.96.36.199. I left all client-side defaults in place except for enabling throughput enhancement (packet bursting).
The Extreme had the latest 7.5 firmware loaded and all factory default settings in place, except setting channel 1 for the 2.4 GHz band and channel 36 for 5 GHz.
I don't have open air method results for the original Extreme because it was tested using the Azimuth method. But the original Extreme still tops the Azimuth method 2.4 GHz charts with average throughput in the 55 - 60 Mbps range for down and uplink.
5 GHz performance was not so great, however, with average throughput in the high-20 to mid-30 Mbps with 20 MHz channel bandwidth and not much better in 40 MHz channel mode.
Figure 5 shows the new Extreme's rankings in the 2.4 GHz Wireless Charts for the average downlink throughput tests with only dual-band routers selected. I was as surprised as you are to see the new Extreme rank so low, with only 25 Mbps average downlink throughput. I'm not showing the uplink ranking; it's just about the same with 25 Mbps average throughput.
Figure 5: 2.4 GHz, 20 MHz mode average throughput chart
Figure 6 shows the 5 GHz downlink rankings, again with just dual-band routers selected. The Extreme still averages in the mid-20 Mbps for downlink, but manages to move up to the top of the 5 GHz uplink chart, beating even the NETGEAR WNDR3700, with an 33 Mbps average throughput.
Figure 6: 5 GHz, 20 MHz mode average throughput chart
Averages can hide a multitude of sins (and strengths). So for a better comparison, I'll use the new Wireless Charts Performance Table to compare the new Extreme with the NETGEAR WNDR3700, Cisco / Linksys WRT400N and D-Link DIR-825 B1.
The Performance Table gathers all the average throughput test results for the selected adapters into a single table. It then highlights the highest throughput value in each Test location for each benchmark test. If results are within 1.0 Mbps of each other then both products' results are highlighted. Finally, the number of highlighted results are tallied for each test group and the product name with the most highlighted values is then highlighted.
You'll note that the Table has been changed so that results are separated for each band and channel bandwidth mode (20 and 40 MHz), which makes for a more detailed comparison.
Figure 7: Wireless Performance Comparison - 2.4 GHz
Figure 7 summarizes the 2.4 Ghz band results and Figure 8, the 5 GHz band. (Click each image to see all the tests in each group.)
No product sweeps all the tests. But the WNDR3700 does the best, winning four out of eight test groups and tying in two more. The Linksys WRT410N and Extreme tie for second, each winning one test grouping and tying another. The D-Link DIR-825 B1 is the only loser, with no wins in any grouping.