Slow going from website to website

When I try to go from page to page, the computer is really slow. Even trying to put something in a cart to buy the circle just keeps going around and around. I have cleaned the cache and viruses and not sure what else to do. It is past midnight, so I don't think these sites should be that busy. Also I have noticed the last week or so the screen with gray out and not let me do anything, until it stops being gray. I have never had this before and have no clue why I do now. Any ideas.

Which browser you are using? Did you tried in different browsers? Some websites may do their maintenance in the night. So it might be a problem.

In my point of view may followings points keep your website slow. html pages that are heavy . - Too many or too large graphics . - Bad coding . - Cart problems . - Slow servers - host issues . - Could be someone else on your shared box that is sucking up a lot of bandwidth . - Are you the only one seeing this? maybe you have a funky router between you and your site.