XPS 8100 not picking up wireless

I have the Dell XPS 8100 and recently changed to Verizon FIOS with the router in another room. The desktop is not seeing the wireless network, even though my macbook, iPad and iPhone all get excellent wireless service when right next to the desktop. I am guessing the problem lies with the wireless card - it is the DW1525 WLAN PCIe Card. What options do I have for fixing this problem? I would be happy to buy a different network card or USB device, but am not sure what would work best.

BTW - I have updated the driver for the card, so that is not the problem.

Many thanks.