One laptop disconnects Wi-Fi on ALL devices

I have an HP Pavilion laptop and use it wirelessly, on our Cox Gigablast service and lastest Panoramic gateway. Almost every time I start it or wake it up from Sleep mode, when it starts, EVERY WiFi connection is disconnected for about 30 sec to a minute. This is the on;y device that causes this housewide disconnect. It does not seem to affect ethernet connections. I have seen a number of these reports on this forum, and it seems that every time, it is an HP laptop (eg, Elitebook). Even if only 3 other active devices are connected, and one person is watching a YouTube, they all go out. I just picked up this modem yesterday. but it happened on the other 2 I brought home. The are no special configurations on the router; I only changed the SSID and Password to ensure neighbors aren't using it. Any help appreciated.