What is eSATA?
November 1, 2007
eSATA is a External Serial ATA interface. Serial ATA is a commonly used interface for internal Hard Drives, and eSATA is an extension of that specification to be used with external devices.
If you’re using a USB or Firewire external drive, what you’re really using is a ATA or Serial ATA hard drive, and an external enclosure. The enclosure has a controller in it which translates the ATA or SATA protocol to USB or Firewire.
This translation causes some delay and there is also some overhead involved in the translations.
eSATA is already in the format that the drive is transmitting. No translation necessary means no lag.
Why Would I want to use eSATA?
Reason #1 - The transfer rate is fast. I mean really fast. Currently there is a 1.5 Gbps and a 3 Gbps Standard. This blows FireWire (IEEE 1394) and USB 2.0 out of the water.
Reason #2 - Less Lag. Since the data is already in a native format, there is no translation involved. This means data gets to the interface faster.
Reason #3 - It isn’t terribly expensive. Maybe this isn’t a reason to use it, but it isn’t much of a road block either. If your motherboard has SATA connectors laying around, you can extend them with a $3 bracket. SATA expansion cards can be found right now for under $30.
Should I replace all of my External Drives?
Sure, and I can give you an address to ship them to. Seriously though, I wouldn’t replace what you already have if it works. When you decide to buy a new drive, eSATA is worth some thought.
There are currently many drives shipping with USB and eSATA interfaces. So even if you don’t currently have eSATA capability, I would take a good long look at the drives with both interfaces, since they would allow you to upgrade later.
Read More:
Serial ATA - Serial ATA International Organization
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Posted in Tech, SATA, Personal-Computing, Hard-Drives, eSATA
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December 2nd, 2007 at 7:08 pm
[…] What is ESATA? - An explanation of the external Serial ATA specification. I know what I’m using the next […]
October 29th, 2008 at 1:03 am
Hi, thank you for sharing your knowledge
My new laptop has an eSATA port, and I have a USB external hard.
Is there any sort of cable that can connect my external hard drive to eSATA port?
and if so, is this faster than ordinary USB cables?
Thank you very much, good luck
October 29th, 2008 at 8:32 am
Well, there are a couple of routes you can go. If you google “esata to usb” you’ll find some converters, although the ones I’ve seen suffer from speed issues.
There’s also the option of buying a new enclosure, disassembling the USB drive, and placing the drive in the new esata enclosure.
The drive inside is more than likely older anyway, and older usually means slower. To be honest, if you get a converter from eSATA to USB, you’ll still be limited by the speed of the USB connection.
If I were you, I would just use it as a USB drive, and then when you’re ready to buy another external drive, then you can look at eSATA drives.
There are also enclosures that offer a eSATA connector, and a USB connector fairly inexpensively.
Hope that helps, and thanks for your comment!
November 12th, 2008 at 11:32 pm
Thanks a lot agian
I think you’re right about “just use it as a USB drive” .
And actually there’s something new for me: I can plug my USB hard right into eSATA port on laptop without any converter, surely the speed is limited but it works.
good luck and bye, Tnx again
November 13th, 2008 at 7:08 am
Well I’m glad I was able to help, but I’m pretty sure that if you can plug your USB cord into the eSATA port, then it’s actually a USB cable your using. Unless your laptop has some new universal connenctor I haven’t heard of. I would be curios to see a picture if you could.
Thanks again for stopping by!
November 15th, 2008 at 10:48 pm
Hi
Ye, surely I’m using a USB cable. actually I meant eSATA port is capable to reseive USB cables too. so my laptop which has 3 USB ports + 1 eSATA, can be assumed as a laptop with 4 USB ports.
I think eSATA port interface is capable to switch its behavior, depending on the sort of cable plugged to it.
If my explanations are ambiguous, I’ll send you a picture of my external USB H.D.D plugged into eSATA port. but how? please send me your email address.
thanks, bye
November 16th, 2008 at 1:40 pm
What kind of laptop is it?
November 16th, 2008 at 9:43 pm
HP Pavilion DV7-1070ee
November 17th, 2008 at 1:06 pm
I looked at the Laptop’s product’s page, and it says that you have 4 USB ports, and 1 eSATA.
If you want to send me a closeup of the ports, you can send it to mike AT port16 DOT com. I don’t see how the USB cable would plug into the esata connector and work.
Thanks.
November 19th, 2008 at 6:36 am
WHAT IS E-SATA PORT
November 19th, 2008 at 7:16 am
The port that you plug your eSATA connector into.
November 21st, 2008 at 7:13 am
” Zenith ” new admirale plus laptops comes with e-sata port.
And there is no need to explain esata which has many advatages over ordinary usb port
November 21st, 2008 at 9:13 am
I didn’t even know Zenith made laptops. Heck, I didn’t think they were in business anymore at all.
Of course there’s a need to explain eSATA. I get hundreds of people every week who come here searching for “What is eSATA.” I do agree, it’s much faster. Of course, USB is still much more popular.
Thanks for stopping by Vicky!
November 28th, 2008 at 12:18 am
Hello All
I have the same problem with Siavash. My Laptop HP Pavillion DV4-1022TX with 2 USB and 1 e-SATA port. The Laptop cannot detect 3G Modem Huawei E172 USB stick, if i plug into USB port, but successfully detected and running if i plug into e-SATA port.
I just knew that if e-SATA port compatible with USB.
But could someone tell me, is it OK to do that ( plug 3G modem USB into e-SATA port), coz i’m afraid it will damage my 3g modem someday..
Thanks
November 28th, 2008 at 11:08 am
Hi,
There is no problem connecting your G3 modem to eSATA port, and It won’t damage your modem. because this port in HP laptops is customized to receive both USB connections and also eSATA. so you can use it safely.
Good luck, bye
November 28th, 2008 at 6:08 pm
Like Siavash said, it’s not a matter of USB and eSATA being compatible, or even that you’re plugging in a USB device to a eSATA port, it’s the HP has 1 port which is made in such a way that it accepts both plugs, and they have their own set of connectors.
I had never heard of it until Siavash sent me some pictures. (Thanks again Siavash!)
November 30th, 2008 at 5:14 am
I believe so.
But another thing, the technician where i purchased 3G modem said that USB port in HP laptop for some series ussualy have problem with USB devices according to his experience. It seems that it doesn have much power to run the USB devices like modem, external HD, etc. Thats why it wont work with my modem.
November 30th, 2008 at 8:41 am
Although I’m not going to argue with him on that, I don’t use HP laptops, since you’re plugging the device into a USB port, and not a eSATA port, then you would still run into the same problem.
I’ve personally seen where a device is only recognized on one USB port, and not any of the others. Sometimes it’s because the device was installed incorrectly in the other port, sometimes it’s just because it’s a little finicky.
Long story short, if it’s working in that port, then you should be fine.
November 30th, 2008 at 7:27 pm
Yup. My USB port still can be used for mouse device.
Thanks a lot for sharing..
December 10th, 2008 at 6:43 pm
I have a tower with SATA hard drives. Can I buy a laptop with eSATA, add connectors or cases, and simply add them to the laptop?
December 10th, 2008 at 8:28 pm
@Robertpri
Yup. To be honest, you don’t even need a laptop with eSATA, if you plug the SATA hard disks into a USB external carrier. The one thing I want to make sure we’re clear, I have 2 points:
1. The hard drives from your tower would be external to the laptop, unless by some small chance the drives are 2.5″ drives, or your laptop takes standard 3.5″ drives.
2. You probably wouldn’t be able to boot your laptop off of the hard drives from your tower.
I have a few computers that I upgraded the hard drives in, and had a few 80G SATA drives laying around. This is exactly what I did.
Thanks for dropping by!
January 2nd, 2009 at 12:28 am
Re: some USB devices don’t work in all ports. It is known that some computers have USB ports that provide significantly less than the correct 500mA of +5VDC. This deficiency is known to prevent larger-capacity 2.5″ USB drives from working unless a special cable is used to draw power from *two* USB ports simultaneously.
One possible reason that dio’s USB modem works in his combo port and not in the USB port may be that E-SATA requires more current to be available.
January 2nd, 2009 at 9:19 am
That’s a good point Neal!, although I don’t see why a modem would need so much current.
Thanks for dropping by!
January 2nd, 2009 at 12:55 pm
Having posted before looking up the ESATA specs, it turns out I am slightly wrong. The ESATA data interface does not draw any power; it is data only. So the only answer left is that the companion USB port just happens to have been built to supply the full 500mA, while the others probably supply closer to 360mA.
Modem needing power. Hmmm. Ah, the Huawei modem is a 3G RF device. I can see it needing almost all of USB’s 500mA current. Y’all’ll recall that 500mA of 5VDC is 2.5W. If the modem is transmitting at 0.5W, it’s entirely possible that it needs all 2.5W to operate.
January 2nd, 2009 at 9:40 pm
Jeez, whack me in the head with Ohm’s law!
Thanks Neal, I wasn’t too sure about the power available on the port.
January 4th, 2009 at 2:52 pm
I have a Sony Digital Movie Camera, Which uses a 4 pen 1394 Firewire cable. My new laptop has the eSATA/USB port. Is this the best way to make this connection?
January 4th, 2009 at 7:34 pm
Sorry Bill, 1394 isn’t compatible with eSATA or USB. You shouldn’t even be able to plug it in there.
Thanks for dropping by!