wireless network drops signal

ive been using a linksys wireless router for about 8 months now from comcast. Its pretty stable and i liked it untill today. I just recieved a new dell e1505 with the intel pro wireless a/b.g as the wireless card. It runs windows xp media center edition. We have 4 computer including the new one on the network now and with the orginal 3 everything worked fine we had a stable network. When the e1505 however connects to the network within 5 minutes all the computer on the wireless lose connection. The e1505 is the suspect here because it seems to be the computer causing the problem any help fixing this would be great because it`s really starting to get on my nerves