Almost never. Seems rather pointless to me. But then, i've gone on about this much in the past. Search and you shall find.

If I've been doing a LOT of messy audio stuff I might defrag, I can put up with stuttery video playback but not audio.
Bob.

I defrag video drives frequently, especially if I am dealing with a disk that is fairly full. I believe it makes things run faster.

I have a 2.4GHz P4, 512MB RAM, so I am on the low end of specs for today's programs. I need all of the help I can get.

Buddy

Up until around a year or so ago the standard question to problems people were posting regarding either their software or their hardware was:
Did you defrag?
I suspect that even those who used to post that nonsense have come to realize that defragging is not a cure-all to problems with either their hardware, their OS, or Vegas.

In answer to your question, if a drive is REALLY fragmented as a result of not defragging in a very long time it can cause a system slowdown that can "contribute to" problems.
I usually defrag after I have removed old video from my hard drives, but after I capture new ones I don't defrag until I am finished with them, otherwise it can take endless hours of wasted time that can otherwise be devoted to editing or waiting for renderings to finish.

John

I've got my system setup to do it once a week at night. Works great.

Just keeps the drives from getting really bad. Until they hit a certain level - it doesn't make much difference, but there is a point where it really starts to impact. Once it gets there it may take 5-6 passes with defrag to really get the drive back in shape - espeically if it is very full.

Defragging weekly and I've never had to think about it.

Daily, via DiskKeeper.

Manually, about once a month. I start with a thorough Disc Scan, then the Defrag.

Once every four-six weeks using O&O.

Never. Ever. Defrag is a total waste of time. There is no testing, on modern computers, that has ever shown any significant improvements on defragged disks (exception: some defrag vendors post resting results done on drives that are "pathalogically" screwed up in a way that would seldom if ever happen in real life).

The standard response to almost any problem, from people that don't know, is: Did you defrag your hard drive? Go back and look at such posts, and in the future, keep the following question in mind: Did anyone ever reply that they had defragged and it had solved their problem? No.

See my previous, recent, more in-depth post:

Defrag 1

Defrag 2

I can't speak to the technical consequences of defragging, but I do know that on occasions when I haven't defragged in a long time, and then perform a defrag, I notice a significant decrease in loading time for applications like Microsoft Outlook. I guess that makes perfect sense as I have a huge PST file, and if the drive were heavily fragmented, it would seem reasonable that loading time would be adversely affected.

Like some of the other folks here, I use Diskkeeper set on automatic and let it defrag regularly so that I'm not tying up my computer to do so. The software is so cheap, and the intrusion so minimal, that it seems like a worthwhile thing to do.

Once I saw a friend's laptop that was very slow because the hard drive was 84% full and he hasn't defragged the drive for years. I think that's the only time I've seen fragmentation to be a problem.
Generally fragmentation problems happen when your drive is almost full, and if you've been using the computer for months.

If you're doing video, it's a good idea to create a partition just for video data. Only put video and project-related files on it, and you shouldn't have fragmentation issues.

It is common sense, defragging WILL improve read/write performance. I recommend Raxco PerfectDisk, it works much better than DiskKeeper (I evaluated several different ones, and PerfectDisk was the only one that could completely defrag my drives)

Also, when you format your video drive, I recommend using 64Kb clusters, this will increase performance (but you will loose a bit of disk space because you must allocate files in 64kb chunks)

Also, Also, defagging can help to identify disk problems that normal chkdsk will not identify. run chkdsk often too though. Run chkdsk /x if you suspect bad clusters.

The 64k recommendation is not a bad one, but beware that some utilities may balk at the "non-standard" cluster size (see for example, Watch those NTFS cluster sizes).

For those that insist on wasting their time (and their computer's time) on defrag, read this short article:

Don’t Become a Defrag Junkie

As the article says, under a few, fairly rare circumstances, you might be able to measure some slowdown. But rarely. And with video files (which are huge) each time you delete those AVI files, it frees up enormous chunks of space on your drive. Thus, you end up with big chunks of contiguous space. Even if your drive eventually gets fragmented enough to cause significant extra head movement, I bet you can't measure it (someone please try to find a site that, other than a defrag vendor's site, that has actually undertaken such measurements).

I don't doubt that the value of defragging is probably overestimated. But as I said, I did notice a significant difference in load speed of Microsoft Outlook (and my 1.6 GB PST file) after defragging a heavily fragmented system drive. It only makes sense that a defrag, in that specific scenario, would improve performance.

That said, regular defragging probably doesn't do much beyond making us feel like we're on top of things. And maybe, over great periods of time, preventing our drives from getting horrifically fragmented.

I wish backing up data was talked about more than defragging :)

Defragging does help a little but backing up your data is far more important :)

If you aren't sure whether to believe in defragging, just run the built-in defragger in Windows and read the actual report to see which *files* were horribly fragmented. If those files are not important to you performance-wise, then don't bother.

I have found major improvement, even on my video drives (smaller scene files, not huge chunks).

Anybody using Outlook with large PST files is playing with fire. Some day you may not even be able to recover that PST.... It's happened to many.

I have about 4GB of Outlook data, but keep the PST file at just over 1GB through aggressive archiving, so the other 3GB are in separate files. Of course I also have Outlook copy the PST file to a second drive frequently.

If anybody knows of a more robust program than Outlook that still has its key features, please advise. Many would be helped!

I'm with Jackie-C-F...back it up. Then, after you've backed up you can delete files. After you have deleted lots of files and added more, you drive starts to get really fragmented. That's when you need to defrag.

Since working with video, I defrag more often. Since I do a lot of deleting after backing up. (I know, i need bigger hard drives).

Diskkeeper shows that I need defragging every few days when I've been busy.

I do it once a year. The hard drives I have hold the entire season's video. after I am finished I then remove the original files (leaving the DVD folders) and defrag the drives. I am now ready for the next school year..

Whenever I am getting READY for a big project, of ANY kind, video or house design, writing a new will, or ANYthing (even watching a mindless TV show), I have prep time that can be put to use. During that time I am not actually using the computer. So, I get started by:

1) I uninstall/remove any programs or files that I have been thinking about junking.

2) I use widers search to locate and delete *.TMP, *.bak, *.bk!, *.bk$, *.jbf, *.asv, *.$*, and _Temp_*.* files. These are the junk files frequently left over from lots of operations that are not needed ever again. They should already have been deleted, but the various programs I use create and seldom clean up. I typically find hundreds of each type. Your list of junk files is VERY likely to be different.

3) Then, to make the supposed gains real, I empty the so-called Recycle Bin.

I do these first three steps periodically even if I don't get to step 4, below.

The above takes, maybe, 5 minutes.

4) Then I defrag. This, of course, can take a while. That is when I get my other work done.

It may not do a whole LOT of good, but if I neglect to do this for a month or more it is quite noticeable when I actually DO the routine.

I like to think of it a "potentially" useful. Sort of like taking out the garbage before it starts to smell too badly, especially steps 1, 2, and 3. Either in part, or the whole routine doesn't hurt, and it might help. One never really knows. But, as I said when starting this post, I am doing something else during the actual defraging anyway.

Further, widers has an automatic setting that does some defraging in the background on the latest OS versions. But, without manually doing steps 1 - 3, first, the computer is just making a neater garbage pile without taking out the garbage.

But, have you actually ever measured before and after? I think there is a serious placebo effect that takes place. Also, you are doing many other things besides defrag, some of which will definitely improve things, like deleting temporary Internet files, which sometimes can number in the 10,000 range. That represents a lot of directory overhead. Next time you are ready to do your defrag, first reboot. Then measure how long it takes to do something. Then defrag, but don't do anything else. Then reboot. Finally, measure how long it takes to do exactly that same operation. Use a stopwatch for both measurements, and be precise. If you get more than a 5% difference, I'd be amazed.

Diskeeper Pro actually tells you how much time you save when reading or writing the most fragmented files if you do vs. if you do not defrag.

Even those who only use the free built-in Diskeeper defrag in Windows can View Log and see which files are fragemented and how many fragments are in each.

I had horrible performance working with a very long video clip, and did a quick Analyze on that media drive, turned out the file had a huge number of fragments. Quick defrag, problem solved.

This thread has been a real eye-opener. As Johnmeyer says, probably a lot of the pickup in perceived speed is "placebo" or imaginary. However, I have Perfect Disk set up to defrag once a week just for the heck of it (hey! I bought the program -- might as well use it!). Anyways I feel a little more comfortable having that automatic defragging going on occasionally but since I'm creating and deleting large avi files constantly, and I usually reload my C: drive from an image every 3 or 4 months, it probably doesn't matter.