I have a Sony vaio 5 year old laptop that has worked fine. After taking it through airport security, it started hanging, to the point I had to format it. No change. It popped up with a smart HD failure message so I replaced the HD. I installed the OS which took 2 days since it kept hanging and freezing on install. Now it has the same problem again. I've ran memory tests, everything is fine. What could this be?