I have 2GB of RAM currently on my machine, and since taking the advice from another member up here, I installed the x64 version on Win 7. Anyway, so I have 4GB of memory coming in tomorrow. The RAM I have installed now is ~800 mhz speeds I think. The ram I have coming in is 1333 mhz, which is the most my board can handle. I've read where if you install different speed memory sticks, it will automatically downgrade and run at the lowest setting of all the memory sticks. So, my question is, would it be better just to take out the 2Gigs I have in now, and just run the 4gigs I'm getting in the mail? OR would it be best to just add to it, and have 6 total? Some friendly advice would be much appreciated. Thanks.