Over the past year my wife has complained that her computer (desk top) has been running slow and some videos would not play, particularly on FB and other social media. I did disk cleanup, defrag and checked for malware, viruses etc. loaded win. 10 all to no avail. She was talking about buying a new computer so I decided to have another look at it. Turns out even though it has a fast cable connection somehow the wifi app. had been turned on. After shutting off the wifi her computer is running fine again. I wonder how may other folks have the same situation and never figure it out?