You can add MOA and GOOC to those search queries and check. I don't think MOA or GOOC had any effect on the search importance. From our database, the highest signups were 2007-2009, so maybe overclocking genuinly was "big" in those years.
CPU-Z is making an interesting curve, though. The only one that goes up in the beginning. Then again, it goes up only to the point where the rest of the curves are going down.