Hey, I currently only have 2GB of 667MHz DDR2 RAM installed in my PC, and I am beginning to find that it is limiting me too much in what I can do. So, I just bought a 2x2GB 4GB kit... Is it possible to have those two occupying a single DDR2 channel and then the one that is already in there just run in Single Channel to make 6GB? Also, is it possible to use RAM from different manufacturers working together? I think I just bought the kit from the same manufacturer as the 2GB stick - crucial - but I don't have access to my PC at the moment because I'm not back home till Friday... I want to do the upgrade this weekend whilst I'm there.