I just ordered some memory for my Macbook Pro. 2 x 2GB PNY. I tried putting them both in - and when I power it up, nothing happens. No chimes no nothing - nothing comes on the screen. It does power up - but just litterally does nothing. I tried it with just one of the sticks in, same thing. Tried just the other stick, again - nothing. I have just, or so I thought put the original 2 x 1GB sticks back in and booted up. I actually put one of the original 1GB sticks and one of the new PNY 2GB sticks in. It has booted up ok and I have launched a load of apps to fill the memory up. Below are some screenshots. Can someone confirm that all 3GB of the memory currently in the MBP is working? And - can anyone help me get it working with both sticks of the PNY? I dunno where I am going wrong. I tried a CMD+OPT+P+R at start up to clear the PRAM but nothing. The memory I am using was supposed to be : PNY PC5300 / 2GB / 667MHz / DDR2 / 200pin SoDIMM Laptop Memory on the sticks themselves the stickers say : 2GB DDR2 800Mhz SODIMM CL5 Any help appreciated. Thanks.