Wireless Router Question

I have the Linksys wrt110 and the other computer has the usb adapter which
gets a very low signal and can hardly get on the net. Would changing to the
pci model do me any good? I do have some other options such as access point
but wondered if this was a viable option also. Maybe I can just take it back
and use it towards the pci one instead since I have only had these a couple
of weeks from Best Buy. Thanks.