Question about external HD

I found myself running out of space with my 120GB 7200.2 Seagate in my dv6400, so I pulled out an old 80GB Seagate 5400 drive from my parts collection and put it into an Apricorn USB case that I used for cloning.

It seems rather slow on USB 2.0, and the processor (TL-58) spikes to max whenever accessing the external drive. From reading various posts, I understand that the max transfer rate on USB 2.0 is 25MB/sec (I'm getting 21.5MB/sec from HDTune).

Anyway, I'm thinking about purchasing a larger 2.5 drive for the Apricorn case. Would buying a faster drive (ie. 7200) be a waste considering the USB transfer limit, and should I just stick to a large 4200/5400rpm drive? I'm guessing that I won't see much performance in any drive tethered to a USB port, correct?

 

You will still be limited by USB performance. Firewire or e-sata are better choices.

 

just look at the speeds you might get with the drive versus the USB speeds, i think 5400rpms are enough unless you go for firewire.

 

Isn't firewire slower than USB 2.0? If not, can the 4-pin port type on my HP lappy accomodate an external Firewire drive made for the standard 6-pin? I am unsure of the major difference between the two interface types....

 

yes and no, firewire 400 is slightly slower in theory but in practice it is faster. i think it has to do with overhead and simultaneous transfers.

and yeah i think u need to buy a adapter cable but it should be fine

 

Its got something to do with CPU or chipsets and transfers via motherboard intarface. USB data is affected by that, while Firewire isnt. In practice as SideSwipe said FireWire 400 is faster than USB.

 

Thanks for the help guys. I guess it would be smarter to just put the drive in a Firewire-capable enclosure instead (and it would free up my USB port again).

 

i would be over the moon if i was getting 21.5MB/sec . USB is notorious for not reaching peak or anywhere near it in application.

 

The problem with usb is that it's half duplex, so the data flow can't go in the two directions simoultaneously and data needs to be packed in small groups to allow interoperability with different devices.
This reduce a lot the maximum theoric transfer rate of 60MB/s to a modest 20~30 MB/s practical.
From what i remember Firewire isn't half-duplex, and the only difference between 6pins and 4pins is that the first transport also the power so it doesn't need an external power adapter.
If you need more speed, go for a firewire (or e-SATA) external enclosure and you will notice the big difference even with a slow 5400rmp disk

Ps: i just tested my own usb hdd with hdtune and it's capped at 15MB/s! (But i use a pci to usb adapter)

 

What if you have a 5400rpm drive in your notebook? Will there be any benefit using a 7200rmp external (with firewire)?

 

Hmm. I guess my results are not as bad as I thought (I was directly comparing it to my 7200.2 internal, which is probably unfair).

On a side note, the Apricorn case requires two USB connectors (one for the data, the other for power). I've been running this 5400.2 PATA Seagate on only one USB port and it works. I assume that going to a Firewire SATA external will require additional power due to my unpowered Firewire port and a SATA drive's higher current draw? In other words, wall socket power would be favorable over the possibility of overloading a USB port?

 

I have gotten 19.5 transferring Videos to a 3.5" External that spins at 7200rpm. It was a friend's 400gb HD.

I tried it on Firewire400 after that and I got about 21.5, but it was also more consistent.

 

how do i know if i have firewire? I have a vostro 1700

 

Check Dell website?? or shouldnt You know what config You have got?? easiest thing check for the port output on the sides of laptop

 

Wow. I am transferring a ton of data to my new HDD and would like to achieve faster rates if you have any advice. Were you using USB for the 19.5? Were you using Vista? What was your config?

I posted a question about this already if you can contribute: http://forum.notebookreview.com/showthread.php?p=2497527#post2497527