People in the 0-20 range are often just trying to get flamed - but there are some gems there. They just have to learn how the forum works, and they then may quickly start writing quality posts. Those that are just nefs often give up, or make a new alias and come back for a fresh start.
People in the 20-200 range are generally in one of two categories. (A) the flame bait who fights back with many irritating quotes, backtracking, and lies. (B) People who want to make Anandtech a better place since they like it. Since there are two extremes, the quality varies drastically.
People with over 1000 are usually off topic posts that really don't take any intelligence to post. So people who visit those forums quickly become golden members but often have nothing to say. So the quality often is quite lacking here.
I tend to find the most informative posts ususally come from someone in the 200-1000 level. It is the people who work full time often in the computing field, who don't have time to waste in ATOT, usually only post in general hardware who have the most quality posts. But since they work full time they also don't have too many posts.
There are exceptions in every category though. The best correlation is usually post length, not post number. Someone who becomes a lifer by stating "bump" or "repost" or something similar in one word posts is usually the worst of the worst as far as quality goes. People who take the time to write decent sized posts are usually writing quality posts.
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