A couple weeks ago I bought extra RAM for my mac, 2x2gb Kingston RAM for my Mac Pro 1,1 Here's the exact place and product I got: http://canadacomputers.com/index.php?do=ShowProduct&cmd=pd&pid=024192&cid=RAM.188 I want organizing some of my files and all and wanted to take a screen shot of my setup with 'About This Mac' being part of it when I noticed my total amount is 4gb, as opposed to 6gb (I have 4x512mb in my mac as well). Looking at system profiler, the first two sticks of RAM which are the two kingstons in the Upper Riser Card, are both showing 1gb of RAM each. How the hell does a stick of ram go from 2gb to 1gb? Er, BOTH? I tried resetting my PRAM (cmd+opt+p+r) and it didnt help, neither did repositionining the RAM in the riser card. I then tried removing all my RAM sticks except for the Kingston RAM, at first the mac wouldnt start. I switched the sticks around in the Upper Riser Card (dimm 1 to dimm 2, dimm 2 to dimm 1) and it booted, but again, it still shows me a total of 2gb of RAM on 2x2gb sticks. Further more, I ran a memory test (1mb and 10mb size) using Rember and it passed with no problems, and still showed a maximum of 2gb of RAM. Any ideas what could it be or should I go straight to the shop and (i bought it instore) and ask for an exchange?