After quite some time online (a few hours at least) I lose my network connection; the circle indicator in the bottom bar does not spin looking for a network, and Network Manager doesn't connect either. The only thing I have found to do is shut down completely and then reboot after a few minutes and it is all right again. Is this some kind of heat issue shutting down the card and/or is it a faulty card, or just something I've got to live with? Sorry if this is a known problem that has been discussed already - I did do a search but couldn't find anything.