Wow, so Apple was the lowest bidder? Interesting. I wonder if anyone put a windows bid in?
You'd be surprised how cheap Apples can be, especially for the servers. I don't know if an actual Windows bid went in, but the x86 architecture was definitely looked at. OTOH, there are very few Windows clusters on the Top 500, and those are low-placed and overly expensive. For some reason, this cluster isn't on the Top 500, but if it were it would be in the Top 10, for only $5.8 million.