Hello, i wish to buy more RAM for my 20" 2.1 GHz iMac G5 iSight. However, when I go through the steps on the Crucial website to find the right RAM, I am not sure weither to choose "iMac (iSight)" or "iMac G5 2.1 GHz 20" DDR2". Both describe my iMac!!! Which one should i choose?? Also, doesn't it seem wierd 1GB of ram is only $68? Thanks for the help!