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Is defragging relevant to improving disk performance anymore?
It used to be that defragmenting a hard drive gave a significant boost to performance. In the DOS days I would even defragment floppies if I wasn't going to make more changes to the files (it took a LONG time, but was well worth it).
Now... I don't know anymore. I know the theory, but over the last few years I've had a "fuzzy feeling" that not only it doesn't seem to help, but things actually get slower after the first defragmentation of a "virgin" hard drive. I'm not talking about flash drives -- I'm talking good old-fashioned hard drives.
Also, I've used third party tools that are able to defragment more files (MBR on boot, etc) or have more fancy features, and I don't know that it makes a difference in performance either. They run prettier, sure, but that's not enough for my pocket.
I don't know if I'm dreaming it. Is there any hard data on this? Does defragment still help in modern Windows?
My experience has been 99% on Windows XP. How about Vista or Windows 7? Is defragmentation more effective in those versions of Windows?