@mbcdaltx 

Extenders work in half-duplex, not full-duplex like when connected directly to a router. If you want an extender to run speeds similar to being connected to the router, then the extender needs to be configured as an access point and an Ethernet cable must run from the router LAN to the LAN port of the extender.

@Tony 

I don't under when I had my old router  with the same configuration it ran at full speed? I have the same problem with my USB adpater  on my laptop, With the  AX50 I can only get 866Mbs. When I go  back to  the  AC router it's 1.3Gbs? I'm trying to figure out if it's an  issure with the router or the adapters/extender? With my ax200 adapter it run full speed.