I already tried Disktrix SystemBooster v2 to this end, but I'm not sure if it boosted anything. (I should give it another try if anyone can suggest a good way to measure its contribution?) I'm currently using MyDefrag v4.2.9 (formerly JkDefrag) as my defragger. Its algorithm refers to layout.ini in the C:\Windows\Prefetch folder for choosing optimal file placement. I assume that's how many defraggers work. Therefore prefetch optimization is doubly important. Is there anything that does a better job of prefetch management than Windows (XP) itself?