I recently purchased one of the discontinued Aluminum MacBooks from bestbuy, and it had been working great until today. Now, when I try to connect to my wireless network, the connection times out. It usually takes me four or five tries to connect, even if I'm in the same room as the router. After I am able to connect, I cannot get more than three bars on the airport signal meter, and the internet and network are very slow and unresponsive, once again, even in the same room as the router. Is there any way I can figure out whether the problem lies with the computer or the router? I don't have any other wireless devices, and all the wired devices on the router work fine.