So this will happen with Safari, Firefox, or Chrome. I'll load a page and it partially loads. For example if I go to a website where there are thumbnails for a list of videos, most of the thumbnails will appear to be black or have a question mark, like the page just gave up on loading... If I refresh, some of those thumbnails will show but then OTHERS will disappear, like it's having a hard time fetching information. So I tried disabling DNS pre fetching lol, no help there. I even replaced my DNS servers with some better ones thinking that comcast was just supplying me with lame DNS servers... I ran ClamX AV to check for a virus and found a couple of mackeeper files and I deleted those, but other than that I am at a complete loss. It's just frustrating that i can't figure it out at this point. Maybe I need to upgrade to El Capitan? I'm running the latest Yosemite version, but this problem has only developed over the last few days and I can't remember downloading anything too crazy.