Control Panel - Device Manager - Networks - WiFi - write down the brand and model then double click on it Drivers Tab - get the version number. Then double click Update Drivers (this may not do anything as MS is far behind certifying drivers).
Then right click on the device and UNINSTALL - REBOOT -this will refresh the driver stack.
Now go to System Maker and look for updated drivers this will be your fall back. Then go to Device Maker's Site and look for even newer drivers.
Download - SAVE - go to where you put the driver - RIGHT CLICK on it - RUN AS ADMIN
second answer There could be an issue with the driver. Cordless phones can create issues but most modern cordless phones (last 2-3 years) usually won't create issues. Since you didn't have problems with the last computer I would first look at the drivers for the device.
Make sure that you get the manufacturer's driver installed - sometimes Windows installs drivers but they aren't a 100% match. If the driver doesn't resolve - try changing the channel(s) used by the router to see if that clears up anything.
A neighbor could have installed a router that is using the same channel and is creating issues with your computer.