You can pick the 200 on ebay for around $1-2k on ebay these days. That being said, I imagine $4k is way to much. You're better off keeping it unless you really want to part with it. From there, you're most likely looking at how quickly you want to sell it vs how much you want to get. That is, unless you really have an interested buyer. With the newer p2 cards coming out, the only thing I'd see of a selling point is really the case, and even then, I wouldn't pay over $1500 for everything. I'd look at e-bay and also the personal classifieds here on the cow.
Sorry, hope this helps
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