I have recently upgraded to 10.9.5 on my early 2008 iMac 2.66Ghz. Model MB324LLA. Clearly a bad move as things are running very sluggish. I don't use it that much, but I really wanted to use Facetime with the family. I am going to upgrade the RAM to try deal with it. I've seen online that I will be able to use 6GB of RAM with this computer. Apple specs say only to use 4GB. Has anyone tried this and had success, fail? Should I be sticking with the recommended? Thanks for any and all advice.