I guess I left out the OS. I plan on using Vista32 and the most I'd really be able to squeeze in is 3gb. I do some minor video converting/editing so I was hoping to get a speed increase with DDR3. I have been kind of up in the air about it though. From the reviews I have read elsewhere a lot of people have said they have seen a pretty good speed increase and were happy they made the switch. Any other input on this would be welcome.