If he has a huge house, I don't think his laptop would be that old and also, the Dell's use the Intel wifi cards. Having all 3 ap's setup for the same SSID is what you should do and don't know why you are having so many issues. I would assume the ap's are on channel 1, 6, and 11 and how is the power setting? Do all these ap's run back to the same switch?
-Scott
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