Ah ha! A Dutch auction (
http://en.wikipedia.org/wiki/Dutch_auction). This might be a good thing for people who can get away with less-powerful servers (and who can't these days?). I can't find the reference I want to find, but a little ways down in
http://www.econlib.org/library/Enc/Auctions.html it says that a Dutch auction does not maximize revenue for the seller. So you have to wonder why the seller is using this auction style.
Dutch auctions are supposed to take place faster than other types, and risk aversion is supposed to make bidders choose a higher price than they would otherwise. Are people bidding on used servers particularly risk averse, or do sellers just want to unload them?