linksys wireless card problems

[bubba3303]

ok i've had my wireless router and desktop card for just over a year and have had no problems with it until recently. all of the sudden my wireless card was showing no more than 4% signal and wouldn't connect. my brother's wireless on his laptop worked perfectly fine so i don't think it's a problem with the router. i replaced the wireless card with a linksys adapter card. now it's showing 50% signal, but still has problems connecting. usually it won't connect and if it does it shows a very poor, slow connection rate. when i try to connect through the software that came with my card it shows about 50% signal, but says it cannot associate with the access point. when i connect through windows, it won't even find my network. i've done everything i know to do. any ideas or suggestions?