wireless problem

EQUIP
1. d-link 713p router
2. d-link 650 airbus card (b)
3. d-link 660 airbus for pda
4. gateway notebook with winxp home.

PROBLEM:
1. developed connection problems with router, cable tech
installed new router/wireless modem and resolved that problem. (
NETGEAR CG814WGv2)
2. now the notebook and pda will not connect to the internet in
the wireless mode. Cable tech thinks it is a software conflict, no
idea what, my firewall and utility suite is systemsuite 7, I can't
connect even with the firewall disabled.
3. cable tech bought a notebook from local office and established
connection with a linksys wireless - b notebook adapter. He had
originally tried a wireless - g in my notebook, neither one
established a connection. So I now have my original d-link air card
and a linksys wireless -g card along with the netgear

QUESTION:

1. My wireless function was working flawlessly until the modem/router
changeout, why would the machine suddenly develop a hardware conflict,
where would I start to try and find the conflict?