Connectivity issues with Wireless 1505 card for Vostro 200S

Hi, I have a Vostro 220S desktop with Dell wireless 1505 Draft 802.11n WLAN mini-card. Several times during the day the wireless connection turns itself off (The wireless connection on my laptop which sits right next to the desktop works fine). When I run the Diagnose and Repair it comes back with a message to turn on the wireless card. There isn't an on/off switch for the wireless card and even after going to Services and restarting the WLAN AutoConfig, the issue is not fixed. The only option is to restart the machine which fixes the problem. Should I change the wireless card or is there a fix? Please help; Thanks!