2-Story Home (built 2009) in USA
900+ Mbps speeds from Modem confirmed
900+ Mbps speeds when LAN directly to DIR-882 Confirmed
WiFi speeds max around 200 Mbps, 70 Mbps when on upper level.
D-Link support said it was because my WiFi receiver on the testing computer was 1x1. Ok, cool.
So I bought a DAP-1860 4x4 AC2600 range extender. Connected the same testing laptop via LAN to the extender expecting maybe 500 or so realistically? Nope. 200 max.
So I can only assume my DIR-882 is somehow limiting transmission to 200 Mbps. I've performed the following:
Factory reset DIR-882 and avoided QoS engine
Tried running with and without Smart Connect on various channels using WiFi analyzer app to determine which to try
Tried transferring a file via local network on WiFi - Same results, about 200 Mbps (25 MBps)
Factory reset DAP-1860
Adjusted antennas on devices to different matching & opposing configurations
Adjusted WAN Port Speed to 1000 Mbps
Adjusted QoS limits to 1000 Mbps but did not assign any devices
Assigned the DAP-1860 to top of QoS
Tried setting IPv6 to Local Only
DIR-882 HW:A1 FW:1.20
DAP-1860 HW:A1 FW:1.01