Slowdown from external HDD

I'm using my friend's 1TB Cavalry USB external HDD to transfer some large files. When I started the transfer, the speed was somewhere around 12 MB/s and the expected time to transfer roughly 20 GB was about 7 minutes. When I came back from lunch, it was crawling along at 1.15 MB/s with an ETA of almost 6 hours. Meanwhile, the computer itself slowed down immensely; I'm typing this from my room mate's laptop. I checked and it seems that the data is indeed being transferred, just very slowly. Does anyone have an idea of what could be causing this slowdown?

 

Always happens to me too..... I would LOVE to know the answer/solution to this problem.

 

Laptop specs, type of OS, data connections, etc.?

In any event, if you are running an AV program, expect data transferring speeds to slow down dramatically.

 

t8300, 4GB, 8800m gts. 7200 RPM both the drive being transferred to and from. USB connection. Win Vista x64 home premium.

I shut down Avira and it didn't change the speed. Should I shut down Windows Defender as well?

 

If the computer is doing any sort of virus/spyware scanning you should shut the program doing it down. scanning an entire hardrive makes the needle jump back and forth and all around between the two tasks rather than focusing on one. also did you defrag the drives first? if it has to jump all around the drive to read or write that will also dramaticly slow things down rather than just reading/writing sequentially.

 

One thing you can do:

Right-click Computer > Properties > Device Manager > Drives

Right-click on the drive in question and go to the Policies tab. Select the Performance option and enable the write cache if the option is available.

I'm sure this won't solve the problem, but it may help.

In the meantime, try another transfer and watch for any high CPU usage through Task Manager. You can use the Resource Monitor to check which process is consuming so much CPU time during the transfer. Maybe you can track down any offending process that is delaying the transfer.

 

Check... check.... and check.

I don't know about the poster... but personally, no matter what it is... the bloody thing just slows down.... all the time... every time.. no matter what. I figured it was something inherent in Vista?

 

It is if you are using Vista without SP1 installed.

 

The drive that I am copying from was defragged about a week ago with no major changes. I didn't bother to defrag the external. I tried Bog's suggestion but it prompted me for a restart; I still have about 3 hours left on the transfer that I've been running. Only 2.5 of the 5 files have been transferred and I don't want to risk losing that progress by cancelling. After that's done, I'll restart and see if any changes are made.

I've noticed that it's not really the computer that slows down too much; it's just the network connection, which doesn't make much sense. I had to close out of firefox completely because each page would take a minute to load, and now I'm on a single-tabbed Opera browser. Task manager shows 15% cpu usage and 64% RAM usage. I'm using Vista SP1. I wonder why it's taking so long. What's the theoretical transfer speed of USB 2.0?

 

480Mbps, though real-world performance is much less, as I'm sure you know.

 

I set it to performance mode and it started out at 40 MB/s and kept up that speed for about 15 seconds. Then, it steadily declined by roughly 4 MB/s and is now sitting at roughly 14 MB/s. This is much better that the < 1 MB/s rate I was getting earlier, so thanks for the help. Why would it start out so fast and slow down so sharply?

 

That speed sounds normal, and I also get the initial spike of 40 or 50MB per second. I don't have an explanation for that.