Yeah, i had the same problem with vista dropping my wireless connection afer a while. what i did was uncheck ipv4 and ipv6 in the wireless connections properties and applied the settings and then went back in and checked them again and reapplied the settings. this seems to have corrected the issue. well that is until my laptop went into hibernate or sleep mode. hibernate and sleep seems to set this wireless issue off for some reason. so i just disabled hibernate and have it set to never sleep. Hope this helps.
-Skippy-
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