Sorry, I forgot to mention that this is in Chrome on the S7. I am using AnandTech theme.
It has happened more since my original post including about 5 minutes ago.
I do not know what ad and I am only guessing it has to do with an ad because when I go to any page I can scroll and browse for a few seconds as the ads are all loading and then boom, everything is blank except for header/footer of the page. The page still seems to stay long enough to accommodate all the replies on the page since I can usually scroll a lot of white space. At first it seemed to only be inside threads but it has happened a few times now on the P&N main page as well.