I had this same kinda of problem with my Inspiron XPS Gen 2 and Mediacom 10/1 service. I found what fixed mine was unintalling the QoS Packet Scheduler from windows, then running TCP Optimizer and setting up optimized settings for you ISP speed, then after loading those into the registry, run tcp optimizer again and go to advanced settings and click custom settings and under Type/Quality of Service, put 0 in Qos: NonBestEffortLimit, put 1 in Tos: DisableUserTOSSetting, and put 240 in ToS: DefaultTOSValue Apply and restart computer. That is what did it for me, also check you wireless cards properties under Windows Device manager and make sure that any power management is turned off or turned to max performance. Hope this helps you, let me know...