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PerfectDisk for defragging tbh, it's the only one now that still offers free space consolidation. No big deal? well actually... diskeeper, oodefrag etc do not consolidate free space (which is why they're so quick) so you can end up with some free space at the front of your drive, the data, and then more free space then some more data then more free space etc after a defrag. Now suppose all the free space added upto 10gb and you save a video file, say 8gb, that will be fragmented from the outset since the will be no free contiguous block large enough for it even though you have only just defragged the drive. PerfectDisk may take a little longer to do the job (a few minutes more not much) but the end result is a lot cleaner.

Defragging can help a lot on partitions/drives where you continuously save and delete lots of small - medium sized files, even though ntfs was meant to be the best thing sinced sliced bread for smart file placement, it ain't :p

Can you scheduele oodefrag and perfectdisk?

You can with diskeeper, thats why I use that, so it will run at any schedueled time, ie. every week or when ever you wish...

-Anerboda

Yes you can schedule perfectdisk, lets you set a boot time defrag too if you want so new files written since the last defrag are quickly sorted out. Heres a link to the manual in adobe pdf format, pages 73 - 107 is where the schedule stuff is covered.

Perfectdisk 7.0 User Guide