So that removes a possible move to 5GHz. I'd change the WiFi card inside or test with some USB WiFi stick.
I've been dealing with Wi-Fi connection issues on my Lenovo Y580 laptop. The connection is lost or extremely slow (although the Wi-Fi icon in the Windows taskbar shows a perfect connection) every once in a while regardless of how many other devices in the house are using the Wi-Fi. It also happens to be the only one which behaves this way. Originally I noticed the issue when the router (Arris TG862S supplied by the ISP) was set to auto channel adjustment. Having scanned the air using inSSIDer Office, I settled for a manually set channel 6 which seems to work best and alleviated the issue somewhat, although it's still noticeable and occasionally extremely annoying. The ISP tech support wasn't particularly helpful as they basically said that it's none of their business given that it points to issues with my laptop instead of their service (which is fair enough, I guess). Any ideas on what could be done?

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