INTERNET SPEED GOES DOWN TO 1/3 ONCE I DISCONNECT ETHERNET CABLE FROM IT ALTHOUGH I AM NEXT TO IT

[P66]

I have done internet speed test with the ethernet cable connected to the computer and without it. Although I am next to the modem/router everytime I check the internet speed. With the ethernet plug into the computer my download speed is 600 mbp, but after unplugging the ethernet cable I run another test and the result is around 200mbp. What it catches my attention is that the computer is right next to the modem/router. Also, other devices further away from the modem/router get speed of 100 mbp. I have moved the modem/router to different location in the house, but no luck. In addition, I have changed the channel on the 2.4 GHZ to see if there is any improvement, but no luck either. I would really appreciate any suggestions. Thanks for your help.

[antinode]

> [...] With the ethernet plug into the computer my download speed is
> 600 mbp, but after unplugging the ethernet cable I run another test and
> the result is around 200mbp. [...]

   What led you to expect a wireless connection, especially one using
the 2.4GHz band, to be as fast as a wired Ethernet connection?

   Have you tried using the 5GHz band?

> [...] What it catches my attention is that the computer is right next
> to the modem/router. [...]

   The computer could be _inside_ the router, and still not get a
wireless connection which was as fast as wired.

> [...] Also, other devices further away from the modem/router get speed
> of 100 mbp. [...]

   Did you expect the speed to _increase_ with distance?

   Why blame the router?  Does your (unspecified) "the computer" do any
better with any other wireless router?

[P66]

 Thanks for your response, 

1) I was not expecting the internet speed to increase due to distance, as you know further away from the modem/ router most like to speed decrease.

2) The computer is an imac, intel core I7, 3.8 Ghz, 12 GB memory, GB512 SSD, 8 GB radeon pro 550 XT graphics if this helps.

3) I have used the 5GHz band too, but still no luck.

Once again thanks for taking the time to respond to why question.