Hello everyone, i am new to the forum and new to macs. I bought a powermac G4 from ebay awhile back but just recently got it up and running. So far i am liking it and decided i wanted more ram then the 384MB it was sent with. So i looked on ebay to find ram, i purchased this ram right here.. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWNX:IT&item=310077909374 I bought 3x512mb and none of the sticks are recognized in any of the 3 slots. I'm thinking the problem is that the ram is high density, can any give me their opinion on it. Also, with pc's there is a way to get to a bios screen, do macs have anything similar to that? Besides the boot selection screen? I forgot to mention, the mac i own is a powermac g4 single 533MHz cpu. Thank you.