eSata 7200 rpm vs 5400 rpm

So yea, my question is: Does the hard drive speed matter when you use external hard drives? Isn't the speed limited by the transfer cable?

 

With an eSata cable it's likely that the hard drive is the bottleneck as an eSata connection is equivalent to the sata connection in your laptop.

 

So eSata speeds are basically equal to sata speeds? Really?

 

If you're using true eSATA, then yes the hard drive's speed will make a big difference. eSATA, in effect, is basically an extension cord from plug on the outside of your computer to an internal SATA port, hence they will have nearly the same speeds.

If you're using USB, it won't make a difference.

 

If you transferring large files data density is as important as spindle speed. For example: WD5000BEVT 5400rpm will outperform Seagate 7200.3 7200rpm.

 

With USB, the hard drive speed does not really matter, as you'll largely be limited by USB's bandwidth. With eSATA, you'll be bottlenecked by the hard drives on either end in a data transfer.

 

That's interesting, so where would I look for the data density info when buying a hard drive? Is there a FAQ for this?

Alright, it seems everyone concurs that eSata would actually be affected by hard drive speed, thanks

 

In the technical data sheets you can sometimes find the info.

For example, most 500GB drives have 250GB per platter. So two platters.

Most 320GB drives have 160GB per platter. Meaning lower data density. Resulting in less throughput if other variables are the same.

 

So the lower the data density, the better?

 

Higher density leads to faster transfer rates.

 

Yes this is correct.

 

Wait... I'm confused now >.< (aren't faster transfer rates good?)

 

No, this is not correct. HIGHER data density = faster transfer rates = better.

 

Sorry to bring this up again, but I just received my enclosure from NewEgg and I was wondering, does a portable enclosure (powered by USB) provide enough power to take full advantage of eSata?

 

There are very few that have no power supply and have eSATA, and those that do many are 1.5GB/s.

If you find one post it hear and we can have a look.

 

The transfer speeds are more noticable if on the OS HDD but if you're just using it as an external backup of sorts, it really doesn't matter that much; space would be the priority I would think.

 

I mean I already have a 1TB external and 500gb external so all I'm looking for is a bit more portable space with my laptop.

The item I bought was a:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817182181

Rosewill RX25-AT-SC-SLV Aluminum & plastic 2.5" Silver USB2.0 & eSATA External Enclosure - Retail

It works fine with my 5400 rpm hard drive but the speeds are far below my externally powered hard drives (to be expected?)

 

The short answer is no. Although in the near future, the eSATA spec is undergoing a change in which it will not require an external power source to power your device, as power will run through the data cable instead (officially coined Power Over eSATA).

You can read more about it here: eSATA to shed the power plug

If you're running it off of USB, yes. After all, you're running your external hard drive off of USB 2.0, which maxes out at a theoretical data transfer rate of 480mb/s.

 

I mean it's being powered by USB and using eSata for transfer but still is a great deal slower then my external ones that use an AC adapter with USB 2.0 as their transfer

So my revised question would be this I guess:
Does eSata matter when you're powering something through USB?

 

If eSATA is being used for the transfers, USB isn't even in the equation.

What are the models of the drives in question?

 

What exactly do you mean by USB isn't even in the question? I think I'm more confused now then I started

 

I mean USB shouldn't be limiting the speed of transfers if eSATA is being used for data and USB for power.

 

Alright, thanks

 

Wait a minute... if you're using USB to provide power to the eSATA data connection, how do you know the data transferring isn't taking place via the USB connection and not eSATA?

I mean sure, you've got eSATA hooked up and theoretically "talking" to the external enclosure, but do you know for sure that the enclosure is using eSATA as the data transferring method and not USB?

 

The USB is split into two, one for power, one for transferring. When I use the eSata cable, I just plug in the one that gives power.

 

e-sata will be much faster than usb...

 

In the external boxes i have the eSata connection is sensed by a ground loop and therefore switches to eSata if the eSata cable is plugged in regardless of USB.

 

This has already been established?