Pages Won't Load Without Several Refreshes?

I'm having a strange problem that I have never seen or heard of. Every time I try to do anything in windows 7 that requires an internet connection, it gives me a "Page cannot be displayed" or "Page not found" message. The only way I can get some pages to load is to refresh them several times, after wich they will finally load.It is not just a problem in IE8, as Chrome, and firefox do the same thing. Windows will not update anymore as it cannot get a connection, and I cannot purchase items from steam or itunes because they give me a "cannot find a secure connection" error. I recently reformatted and the problem still persists. Other PCs on my network do not have the same problem. I recently moved all of my components to a new chasis, and am wondering if the ethernet port or controller could have been damaged