A couple weeks ago when I did an xbench test, my startup disk got around 110. Now I get around 80. Results for Sequential Write 4K blocks is now around 45 mb/sec instead of around 70 mb, and almost every result has a similar change in speed. The only thing I can think of that's different in the computer is an additional 4GB of ram.. but I don't see how that could have anything to do with this. I don't notice a difference in computer performance. edit: I also just noticed, to my astonishment, that my startup disc now has 40GB more free space than it did a week or two ago. I did not delete 40GB of data. !?!?!