Network connection problems, possible IP conflict (I award best answers)?

IP conflict ermm well unlikely well okay NO. its not.

Wireless operates a scheme or technology known a CDMA - Contention Detection Multiple Access

What your reporting seems to be a high level of collisions in the wireless network, this occurs when two device attempt to talk simultaneously, when this occurs a back-off process is invoked and the devices wait a random time after the network has entered this collision state. These time are of the order of milliseconds and are usually imperceptible. Device normally don't hog the network as the bandwidth is massive 54Mbps much higher than any normal home connection to the internet. A high level of collisions definitely creates this impression of a device hogging the network though, and can eventually lead to the network backing-off for longer and longer time periods, which you definitely will notice.

Okay so if all that made sense, one reason I think you have this is because of what is known as a broadcast storm , broadcast messages are a normal part of any network , and are repeated basically except not on the link they were received, thus propagating to all part of you network. The level of these messages is accumulating and consuming your available bandwidth. The origin of these message could be a piece of malware, this is one possible reason.

Another reason signal strength, wireless is not x-ray. Reposition your router , if two devices are trying to connect to the same access point in a similar space where the signal is heavily blocked it might cause sufficient packet loss for devices to jump in when they think the network is quiet, thus causing these collisions, routers manage weak signals by all sort of coping mechanisms including dropping the transfer rate to compensate for lossy connection. Multiple devices can literally stand in front of one another barring the device behind the other. An old device might cause the router to drop down to b-standard which has low bandwidth to maintain compatibility, not all router are sophisticated enough to produced g and b and n simultaneously.

Try and hard wire some of your devices this will free up the wireless bandwidth and make sure that device has access.

And if all else fails slap your room-mate for hogging the connection and lying when he says he can't get on.

Good Luck

I do have self belief the problem is which you attempt to run 2 routers off of a million connection with a million MAC tackle. you could't have 2 routers with an identical I.P. attempt putting the router I.P as something diverse.