I have a really weird problem. On my HP 4530s probook laptop with i3 processor and Atheros 9000 series wlan windows 7 worked well. I have upgraded to Windows 8 pro.
When connected to power everything works fine. When on battery power Windows 8 connects to my modem but says no internet connection. To connect to internet I have to plug power cord in.
Only on Windows 8. Had no problem with Windows 7.
Just to be sure when it says no internet connection, I checked on my Asus Transformer and it connects fine. As well as my Linux computer.
Only happens Windows 8 and battery power.