I've been using Perfect Disk since late 2009. It's the best defrag tool on the market, paid or free. It's boot time defrag option defrags what the rest doesn't, the system & page file. These files cannot be defragged while Windows is running. I run this option once a month.
Another great thing, is that your files defrags as you go, through it's Intelligence Write, preventing fragmentation before it begins. The user can't go wrong with Perfect Disk. It's my favorite utility.
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