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I recently got an alienware 14 laptop, and want to use Linux on it. I installed Ubuntu 14.04. However, I found that the wireless adapter does not work - Killer Wireless-n/a/ac 1525 Wireless Network Adapter.
So I purchased usb wifi adapter. Now I can connect to Wifi, but extremely unstable. After I have been connected for about 5 minutes, it still says connected, but cannot use internet. I tried to ping a random address, there is simply no echo, rather than no response - nothing echoes in my terminal. If I disable wifi and enable again, sometimes it will connect for another 5 minutes, sometimes just fails to connect.
I thought it was a problem of the usb wifi adapter, so bought another one for raspberry pi, but exactly the same problem.
I thought it was a problem of my Linux distribution, so I tried Ubuntu 12.04, Linux Mint, Fedora 23. All have the same problem.
Still cannot use WiFi on Linux, on my ALienware 14 laptop. Feeling frustrated. Anyone could help? Thanks.
Results of lspci -knn | grep Net -A2:
03:00.0 Network controller : Qualcomm Atheros Device [168c:003e] (rev 20) Subsystem: Bigfoot Networks, Inc. Device [1a56:1525] 04:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5227 PCI Express Card Reader [10ec:5227] (rev 01) Subsystem: Dell Device [1028:0685]