It's a laptop so it is an option to test wired. Laptops are mobile.
Try it at 10 to 20 feet from the router. The more feet, the more probably you will see WiFi issues.
There are folk that install other protection software and miss that it can cause this.
There's also torrent users which come under attack from the web. I don't write at length because of how much is on the web about that.
The story is incomplete, there's some tests that help a little so try a few things before you call the maker. Get ready for that call because they will have you factory reset the laptop.
I'm getting erratic and usually low download speeds. I have a 6 month old Asus UX305LA running Win 10 version 1511 with 8 GB RAM & Intel i5-5200U CPU. Comcast is my ISP I have an Arris DOCSIS 3.0 modem/router. I'm connecting via wi fi (only option with this machine). The wrinkle is that my wife's 3 year old MacAir works great. Speed tests with her machine show a flat graph with optimal speeds. The graph when I do a speed test looks like the Himalayas with peaks far from optimal. Tests done side by side. So I'm thinking it's my machine that's the issue but what can I do about it? I ran a Windows diagnostic with no improvement.

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