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I use Windows Vista 64-bit and I have 6GB of RAM. Today I installed a new harddrive, and started with moving 465GB of data from my old harddrive to the new one. This process is very slow, the speed is 10,5 MB per second and I'm not doing anything else on the computer. The estimated time is 12h for this process.

Why is it so slow?

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How old is your old drive? Have you checked it with HDTune? – nik Sep 8 '10 at 13:15
@nik: It's a Maxtor DiamondMax 11 500GB SATA 3.0Gb from 2006. – Jonas Sep 8 '10 at 14:14
up vote 5 down vote accepted

Actually your speed is 10.5 MB/s not 10.5 Mb/s (bytes vs bits). Depending on the age of your system and components and the nature and quantity of files thats not a bad (or at least not uncommon) overall transfer rate. Since you didn't give ANY specifics I'll stop here.

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Additionally, copying/moving files is highly dependent on the size of the files to be moved. Usually, on large file is copied much faster than a lot of files with the same total size. – Martin Sep 8 '10 at 13:55
But copying a large number of files depends on many other factors. – harrymc Sep 8 '10 at 14:01
You are right, it was a typo by me. But I think that is still slow. The file sizes are around 250-850MB. – Jonas Sep 8 '10 at 14:16
I have now installed Windows 7 and moving back the same data took 2.5h, in a speed of >33MB/s so I think it is Vista that is really slow on this operation. – Jonas Sep 12 '10 at 18:12
I moved off Vista to WIN7 as soon as the RCs came out. Have never found a reason to regret that move, and several reasons (like your examples) to recommend it. – hotei Sep 13 '10 at 14:58

1 - You are restricted in this operation to the SLOWEST speed of your read/writes on either of the drives. If drive A is 100MB/s read and 50 MB/s write and Drive B is 100 MB/s read and 10 MB/s write, you can only copy to drive B at 10 MB/s, no matter how fast drive A is.

2 - Vista copy is slow in general. You can use xcopy or robocopy from the command prompt which will be much faster.

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One of the main complain about Vista is the slow file copy or move operations. It seems that it is the new "Remote Differential Compression" who is the culprit.

To turn it off go in Control Panel / Programs and features / Turn on or turn off Windows features and uncheck "Remote Differential Compression".

EDIT: Alternatively, you can install the Update for Windows Vista for x64-based Systems (KB938979) which Microsoft released to address the slow move/compression issue.

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I don't see KB938979 addressing this specific condition ( And, I don't think a rsync like behavior will be applicable when the target drive is empty to begin with (no previous 'version' of data). I also think this Windows 'move' will not be trying to compress before transfer. – nik Sep 8 '10 at 13:23
I turned off "Remote Differential Compression" but it didn't help me today when I am transferring another 410GB of data. – Jonas Sep 9 '10 at 7:43
You are right about Vista. I have now installed Windows 7. Moving the same 465GB data that took 12h (10.5MB/s) took 2.5h (33MB/s) with Windows 7. And it was between the same harddrives. – Jonas Sep 12 '10 at 18:09
I have now the same problem with Windows 7. I only have a speed of 13-14MB/s. I think this is because of fragmentation. This probably goes away if I install a SSD-drive. – Jonas Mar 13 '11 at 19:13

The most common way to slow down any hard drive is to have too many individual streams of data too and/or from it at the same time.

I find and can prove, that copying from one drive to itself is exactly half as fast as from one drive to another, depending on the hardware obviously, equal drives and such.

This is a huge timesaver if you are extracting a lot of data from one drive to another, basically never extract from one drive to itself, it's twice as fast or more to extract archives to a different drive to save half the time.

Some of the newsgroup downloading programs like "grab it" have a 'folders' section where you can specify to download to one folder on one drive, and then extract to a different drive/folder, I find this saves a lot of extract time.

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You shouldn't use Windows Explorer for large copies : It's the planet's slowest copier.
Use any Explorer replacement that doesn't come up with Explorer's silly copying dialog.
My own favorite is the free Servant Salamander 1.52.

If you have an antivirus, turn it off, since it will insist on checking every copied byte.

And finally: If your 12 hours estimate is based on Explorer, be advised that its estimate is normally quite wrong.

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Use TeraCopy , it is a compact program designed to copy and move files at the maximum possible speed, providing the user with a lot of features

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I am leery of quoting from the developer's website directly in describing something. It indicates that you haven't actually used the product... – JNK Sep 8 '10 at 13:51
Well I am using it for years, and I am very well satisfied. A rarely suggest a software if I don't have some personal experience or find anyone thanking that software in some other forum – subanki Sep 8 '10 at 13:59
It's good you have! Personally I just like to see what you think from your use of it instead of the text from the webpage. When I follow a link and see the EXACT same description it gives me pause. – JNK Sep 8 '10 at 14:19
TeraCopy is good. I am not sure if it will help in this condition (have not yet figured this problem yet). But, if you can give it a try the data will be useful. – nik Sep 8 '10 at 14:22
@JNK its just that i was going to type those in my words but felt lazy and copied it – subanki Sep 8 '10 at 14:28

My solution was simply going into Control Panel → Network and Internet → Homegroup and I simply left the homegroup.

My speeds often started out as high as 30 MB/s and would drop to as little as 100kB/s in about 10 seconds and would actually still decrease in speed, but since leaving the homegroup my speeds are back at 20MB/s+ and holding.

Another solution is of course reinstalling Windows but let's be honest, this is not a solution and should only be done if you reach critical stress and frustration.

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