Not sure which Macs use PC2700 memory, I was buying for my Dell. I've been waiting for prices on 512MB sticks to come down after they skyrocketed from the graphics card dulge. Today I checked and prices were getting back down to what they were five months ago, then I plugged in a 1GB search to see how much higher they were and found this deal (check out the price at etronics). It's only twenty bucks more than the best price for a single 512MB stick of the same memory (brand and chip, model numbers match). Just placed my order.