photonboy :
availabilty, thus price gouging.
Quick 101 on economics and how modern web stores work.
First, the stuff you see for sale on Newegg isn't all sold by Newegg. They sell "retail web space" to other sellers, whose products show up along side Newegg's when you search their site. To see stuff which is actually sold by Newegg, scroll down the filters to "Seller" and check only Newegg. You'll see that their price is still around $250. (Newegg isn't the only one who does this. Amazon, Walmart, Sears, and most other big sties also do it.)
Second, this isn't price gouging. Gouging is when a seller increase prices in response to a spike in demand or a drop in supply. What's happening here isn't gouging. What's happening is how the market works - how it "adjusts" prices even though there's no intelligence behind it. Newegg sold the cards for around $250. Other sellers priced them around $500-$600.
People simply bought out the lower-priced cards (the ones sold by Newegg). Once Newegg was out of stock, the only cards remaining were the higher-priced cards. In other words, the sellers aren't the ones increasing the prices in response to increased demand. The prices are actually being increased by
buyers - they're buying up the lower-priced cards until the only ones left are the higher-priced ones. Thus causing the market price to increase even though no seller has increased their prices.