PC Lock Problem Solved, It Seems

On Tuesday, I changed my keyboard and USB hub to new ones. Since then, no PC locking problem has taken place. And even the web connection speed looks better. The culprit seemed to be a loose wire connection of my old USB hub. I know that the wires inside the connection cord to the PC were in a precarious condition as to get exposed. But then, what things does the USB connection have to do with my net connections?