I am using a W7 Ultimate 64 bit install on a custom built machine. EVGA Z68 SLI motherboard with an Intel i7 2700K and 16 GB of RAM. I'm not overclocking and don't have any heat issues being reported on the system including my GPU.
My problem is baffling me. If I were to steam a movie on my system, my computer perfomance seems to drop significantly. My mouse will jump all over the screen if I try to close a window. Strangly enough, if my kids stream a movie on my wife's laptop, my desktop performance drops as if the movie were streaming on my computer.
I've done speedtests on my PC while streaming a movie on my wife's laptop and I am getting good results. I don't know where to begin.
I understand you pros are all volunteers and I certainly appreciate all the help you provide. I look forward to hearing from you to figure out this strange issue.