I have an Acer Aspire 5520G and recently I had a big problem with it. A couple of days ago I was watching a video on the internet and my laptop froze. I had to shut it down after waiting a couple of minutes and when I wanted to restart it, it acted normally for 2 seconds then it restarts automatically over and over again. I can only shut it down by unplugging it. Nothing appears on screen. I think that it is a hardware problem. If you need further information please leave comment.