Slow Data Transfer Speeds...USB and eSATA

I have the strangest problem. I just purchased an eSATA external HDD and the fastest steady transfer rate that I can get is between 38-39mbps. It will start out at 50-60 and within a couple of minutes throttle down to 38-39. On a couple of occassions I see a spike for 100+mbsp, which will last for about 20secs, but then it starts the slow steady slide down to 40mpbs. Is there some setting that is causing this? I have searched this board and googled this problem and I have tried everything but nothing seems to improve the data rate.

 

Is this going from eSATA to USB? If so, that doesn't really sound far from what I would expect.

 

Huh? Isn't there a eSATA cable. So you need a eSATA in and out. Can't do eSATA with USB. Or am I totally mistaken.

 

Well the topic title says USB to eSATA, so I was assuming the OP is doing a drive to drive transfer. I was saying a transfer from an eSATA drive to a USB drive.

You are correct that eSATA and USB are totally different interfaces. eSATA is really just regular SATA when you get down to it.

 

Oh, I thought about that too when I read the title, but then again, usb flash drives hardly hold much space unless u have the 8gb-32gb ones which get pricy for that amoount of space. And he described it like hes transferring large amounts of content to be something so small to a usb drive. I figured he meant he got a USB 2.0/eSATA external hard drive; not that he was actually using a usb drive.

 

I do not mean a USB flash drive, I mean an external USB hard drive. You know, it's possible to copy from one external drive to another, even cross interface. For example, sometimes I need to copy things from my Seagate Freeagent Pro (eSATA) to my WD Passport (USB). USB drive does not mean USB flash drive.

PS - a 32GB flash drive is only like 50 bucks, I wouldn't consider that expensive. But the speed would be more like 8-10MB/s in most cases if you were copying to the flash drive.

 

Of course. I know what a usb external drive is, I must have misread. Anyways, still no clue what the OP is talking about. Whether he has both a usb and esata drive and transferring content within those two to each other, or just using 1 drive that has both usb and esata connections and getting bad speeds.

 

Just to add to the OP's post here...

The transfer speed will fluctuate depending on file size.

Larger files will be transferred faster than smaller files with the same overal size.

About USB speeds:
On a 7 USB Hub I get about 7MB/s max from my laptop - about 3-4MB/s between drives, and on a 2,5" USB HDD I can get up to 18MB/s

PS: Isn't this more a hardware question?

 

Sorry guys...didn't express myself well. I am getting slower than expected transfers from both eSata and USB. I purchased an eSATA express card (eSata expresscard to eSATA hdd) to improve transfer speeds for large media files (vs. USB). The speeds are faster than USB, however only by an order of magnitude of 2-3X. The same thing happens for both USB and eSATA transfers...starts off high, then throttles down. I don't think its a hardware issue because it is happening with both a native (non hub) usb port and an expresscard eSata connection. Btw, the files are between 4-6gb.

 

Hmmm....well same for me - they do slow down a bit after a quick start...

What speeds do you get for
a) USB
b) eSATA
??

(not from ext. USB to ext. eSATA but say int. HDD to external HDD)

 

USB (to ext. USB HDD): Best-10mbps, usual 6-8mbps
eSATA (to ext eSATA HDD): Best 8-mbps, usual 38-39mbps

 

For large files USB is a touch slow - for small files its about right...

 

Just a small nit to pick, but "order of magnitude" refers to powers of ten.

So your "order of magnitude of 2-3x" would imply 100 to 1000 times. I actually think you would be quite happy with THOSE numbers... big ol' grin...

Gary

 

By "mbps" I take it you mean MB/s and not Mb/s. There is a big difference between bytes and bits. Also for best, do you mean 80 MB/s? I think you need to be more clear about your situation, for example what laptop are you using? What is the make/model of your expresscard eSATA? Are you transferring big files or small files (how many MB or GB)? For sustained USB transfers of lots of small files, my Patriot Xporter 8GB gets around 10-15 MB/s but with a single large file, easily double that 20-30MB/s. I have a SIIG eSATA Expresscard and transfer files from my WD6400AAKS external hard drive at speeds around 30-40MB/s for small files and 60-80MB/s for large ones. HDTune of the hard drive gives an average of around 90MB/s.

 

Answers:
1.) MB/S
2.) Filesize (stated in prior response): range from 4 - 6g/file.
Note: Primary use to backup media server used to house movie files...initial b/u is around max at 930gb, but yesterdays initial transfer (new drive) was ~ 400gb, future transfers will be about 4-24gb.
3.) Card: Rosewill RC-605 SATAII ExpressCard - 2 x SATA
4.) Drive: Fantom G-Force GF1000EU 1TB USB 2.0 / eSATA External Hard Drive
5.) PC: Sony Vaio FW245 (Black Friday Best Buy Special) w/ upgraded HDD (Western Digital Scorpio Blue WD5000BEVT 500GB 5400 RPM 8MB Cache SATA 3.0Gb/s Notebook Hard Drive)

 

Try running HDTune to see if your speed is capped (if it flat lines).

 

What setting or software application would "cap" transfer speed?

 

It would be hardware cap most likely if it flat lines. An example is if you connected your external via USB and tested it. It shouldn't cap on eSATA unless there is an issue with the controller.

 

HDTune Test - eSATA DRIVE:
Max: 90.5
Min: 42.3
Avg: 68.7
Comment: Graph starts high and continues on steady decline down, no flatline but clearly something is driving it down.


HDTune Test - WD HDD
Max: 79.5
Min: 22.3
Avg: 57.7

 

All of those speeds are perfectly normal.