Thanks for all of your comments. I've passed through that airport (PIT) with the same laptop at least once every three months since the problem occurred and nothing has happened. This occurred in December 2002 when there the security level was at Orange due to some people that the FBI was searching for, I had a hunch that if the detectors were put on their most sensitive setting perhaps this corrupted the DRAM chip.

Unfortunately I can't pin it down to TSA since I was past security and flying in the air when I discovered the problem. As 'flymeaway' mentioned, at high altitudes there is a higher dose of EMF radiation.

One thing that irked me was the laptop was not under my constant survellience when this incident occurred. Back in Dec. 2002, TSA had one guy frisking me with the wand, while another guy took my laptop away to get scanned. During those 30 seconds or so, I don't know whether the laptop was dropped. Learning from their mistakes, TSA now makes sure your valuables are under your constant survellience.

I think what I will do from now on, even though its a hassle, is to
1) Boot up the laptop before passing through security.
2) Show the laptop to a TSA employee, proving that it works.
3) Shutdown the laptop
4) Pass through security
5) Boot up the laptop again to make sure it works.