Do you have a wireless mouse or keyboard?
Download, run, and ATTACH (using the paperclip under the toolbar) the results of this utility:
Hi, I have a keyboard.
It is possible your Wireless keyboard is interferring with your WiFi. Both operate at 2.4Ghz.
Remove the wireless keyboard and dongle. Use a wired keyboard to test.
Turn off your bluetooth and test.
It improved a little bit. Thank you.
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