Probably a torrents issue.
When you're downloading a torrent, others on the torrent network can be downloading from you.
As that number increases, your available bandwidth can decrease significantly.
Your connection can slow down simply by having open connections.
You might look into tweaking your torrent config.
In post #7 though you have labelled "mine" there seems to be another device of yours connected just above.
And now you tell us us you use torrents which means that is using download and upload speed.
"just bought an adapter to catch 5ghz signals. It is doing its work and Speedtest is showing 70+mbps speed, "
That won't make any difference on 70 Mbps as your 2.4 GHz will do around 150 Mbps.
Everything will share that 70 Mbps, all devices and services connected.
Some Modem/Routers have QoS which enables some configuration of priorities. Some downloading applications can restrict their speed to a smaller proportion of the total so you can continue to use other stuff like a Web Browser.
With my Modem/Router they list some preset QoS policies for various services including 3 or 4 torrents. You can select and add your own if something is not listed.
That above connection is probably 2.4ghz network. I use tenda router which throws 2 frequencies. Since my laptop is old it doesn't catch the 5ghz network, thus, I purchased one device. So you saying that the device won't be useful? It is connected to 5ghz now. Plus, can't see any QOS option in my router settings, had this in previous router.
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