wordpress or mu choice from server load perspective

I am sure this has been addressed before, but I am having trouble finding the answer that suits my specific question.
I have 1 dedicated server currently, and I am looking to set up a bunch of new blogs. Some are open for public posting, some for individual authors to write their own blogs. My questions is, what makes more sense from a server load perspective ?? Installing several different wordpress installations with separate mysql DB’s … or 1 install of wordpress MU to manage it all. I am not concerned about having 1 admin, or any of that … just wondering which way will work best for performance on our server if I set up say 10 blogs.
Thanks,
Jesse