What am I missing here, is this a misprint? http://eshop.macsales.com/item/Other World Computing/53FB1GD4GBK/ I went to check out memory upgrades for my mac pro and they have a big chart showing all the memory upgrade prices. I noticed one of the options was much lower per GB than the rest. I've read over the description 10 times. What am I missing? There's got to be something I misread, or they goofed.