linksys wireless

I recently purchased a WRT54G wireless router. I installed it when I had Win XP. It worked great, excellent signal strength. When I switched to Vista, my connectivity dropped to Fair and sometimes to Limited. There are no obstructions. I changed nothing except the OS. The linksys tech support site was so busy they shut it down, as they say, to serve us better! My computer is an Acer laptop, Aspire 5050. Any suggestions on how to boost signal strength? Is it something to do with Vista Settings? Any help would be greatly appreciated.

try this MSBBN: How to troubleshoot wireless connection problems