On my desktop, not old, windows 7, the internet connection keeps going out for like a minute or two, a bunch of times a day. Its not disconnected totally, just has that little yellow exclamation mark. My iphone which also uses wifi is just fine, as is every other device in the house. I updated driver for my adapter a year or so ago but that didnt fix the problem (this has been going on for a while obviously)
Read more: Wifi dropping constantly, on my computer only?