Sold listings on ebay point to an average selling price of $125-150 for the Q9550S, some of which came with motherboards. The 45nm Yorkfield chips didn't seem to be very popular and were released quite late. Most folks went with Nehalem CPUs, so the low number of C2Qs from that era likely keep the prices high. The 65nm Q6600 was far more popular, easy to overclock, and can be had for cheap. I have a X38 based system I would like to upgrade myself, but with the high cost of CPUs and DDR2 memory, its likely to get replaced completely at this point.