Yeah, it may be that one of the sectors in the RAM has gone bad. If you have more than one stick, try using them one at a time, then, test-run your computer. Naturally, the stick that fails is the faulty one....
If you have more than one stick, and they both fail, chances are, it's a virus problem rather than a RAM problem... At this point, try using a different stick in your computer, and if it doesn't work, you're probably looking at a virus problem. If the other stick of RAM does work, then you indeed have a RAM problem.
If you only have one step, you can still do the process I listed right above (Use different stick), and if the other stick causes a problem too, you have a virus problem.
Hope I helped!