Wireless signal goes weak

My wife has now moved her desktop in to our room. Away from the Netgear router. My MacPro and it's airport works fine picking up the wireless signal in there. But the desktop is acting up. If you shut airport off, then turn it back on, it shows max strength. But after about one minute, it drops down to almost zero. Loses internet connectivity. My Netgear router is in another room in the house, but in a cabinet. But heck, I can see my neighbor's wireless two doors down. Works fine on the laptop, same room, but drops like a rock on desktop. Thoughts? Thanks