eSATA/Firewire/USB - External HD Speed Question.

[BrittQ]

Can anyone verify this one way or the other. Here is a copy of what I was told on another forum.

"As a rule, we choose either to go SATA, which requires no bridge board, or we go Firewire and USB. The reason being that ALL enclosures that have both SATA and USB or FW connectors bridge the data from the drives to Firewire and then back to SATA. This means the SATA port on the drive has every weakness of the Firwire or USB port and none of the advantages of just plain old fast simple SATA.

We never recommend nor use USB for hard disk data transfers. USB was never intended for that use and does it supremely poorly. USB is great for keyboards and cameras, horrible for high speed stuff. So stick with SATA or Firewire.

And if you can go SATA then just go SATA. SATA is simple. A SATA bus uses no bridges, it talks to the drives using the same type of data transfer protocol that goes over the external wires. Simple and faster.

Any time you add in a bridge, like a Firewire USB bridge, you add complexity. This means it is slower and less reliable. More ways to fail."

 

[stomer]

Can anyone verify this one way or the other. Here is a copy of what I was told on another forum.

"As a rule, we choose either to go SATA, which requires no bridge board, or we go Firewire and USB. The reason being that ALL enclosures that have both SATA and USB or FW connectors bridge the data from the drives to Firewire and then back to SATA. This means the SATA port on the drive has every weakness of the Firwire or USB port and none of the advantages of just plain old fast simple SATA.

We never recommend nor use USB for hard disk data transfers. USB was never intended for that use and does it supremely poorly. USB is great for keyboards and cameras, horrible for high speed stuff. So stick with SATA or Firewire.

And if you can go SATA then just go SATA. SATA is simple. A SATA bus uses no bridges, it talks to the drives using the same type of data transfer protocol that goes over the external wires. Simple and faster.

Any time you add in a bridge, like a Firewire USB bridge, you add complexity. This means it is slower and less reliable. More ways to fail."

It's pretty much correct. SATA is a protocol built specifically for data transfers. Unfortunately there aren't any Macs out there with eSATA connectors. As the article says, in lieu of SATA go with Firewire if possible.

 

[Sun Baked]

USB is cheap, because it is sold in high quantity to PC users.

If you are going to use it for occasional deep backup or storage, it is fine.

If you are going to transfer a lot of data daily and/or work on the drive daily -- it pays to get a FW drive.

Backing up a drive daily to USB is going to make your head bleed and possibly leave portions of your head in the keyboard.

However you may have to hunt the shelves a lot hard to find the drives with the FW ports -- and some stores may not carry them, I know CompUSA is quite limited on their FW external HDs in some stores unless you want to buy the empty external cases and make your own. Basically hunt around, they do have them in store locally, I think Best Buy, Target, and some others.

 

[irm16]

eSATA Adapters for the Express Card slot

Any references or stories about eSATA expansion cards for the Express Card slot in Macbook Pro's? I've considered this; I'm not sure how well they work, if at all.

 

[BrittQ]

I'm going to build my own - put together an enclosure and drive. What I want to know is if there is any difference in having an enclosure that is only eSATA and one that is eSATA plus usb/firewire.


"As a rule, we choose either to go SATA, which requires no bridge board, or we go Firewire and USB. The reason being that ALL enclosures that have both SATA and USB or FW connectors bridge the data from the drives to Firewire and then back to SATA. This means the SATA port on the drive has every weakness of the Firwire or USB port and none of the advantages of just plain old fast simple SATA."

It's pretty much correct. SATA is a protocol built specifically for data transfers. Unfortunately there aren't any Macs out there with eSATA connectors. As the article says, in lieu of SATA go with Firewire if possible.

What about MBP express34 SATA Host Cards?

 

[maberga29]

I had a similar question a month or so ago when getting an external. However, the research I did didn't quite agree with what you've quoted. I found that--at least in the technical specs for the enclosure and HDD--eSATA connections did not vary in speed depending on whether there was a FW or USB with it.

i.e. the data transfer rates of the eSATA connection for drives that had only eSATA and drives that had both eSATA and FW were both quoted at 3.0 Gbps.

I'm also looking into an express34 eSATA card for my MBP, I was very excited when I heard about it. Does anyone use one now or can attest to it's speed?

 

[velocityg4]

Expresscards

Any references or stories about eSATA expansion cards for the Express Card slot in Macbook Pro's? I've considered this; I'm not sure how well they work, if at all.

This Rosewill RC-605 should work well. It has solid customer reviews on Newegg and is Mac OS X + Windows compatible so it should work with bootcamp as well. As for an enclosure this Thermaltake EA3006 is eSATA only. But from the reviews I have seen on Tomshardware guide do not reveal any appreciable difference in eSATA only enclosures vs eSATA + another port when the eSATA is the connection being used.

 

[tmoney468]

I have the Bytecc eSATA expresscard and it performs really well compared to usb. Here's where I got it from:

http://www.directron.com/bteces2.html

The only thing I had to do once I popped it into my MBP was to download the SIL3132 Mac drivers from Silicon Image and it worked perfectly. Bytecc is a good company, I have many external HD enclosures from them and they've all worked wonders.

 

[maberga29]

I have the Bytecc eSATA expresscard and it performs really well compared to usb. Here's where I got it from:

http://www.directron.com/bteces2.html

The only thing I had to do once I popped it into my MBP was to download the SIL3132 Mac drivers from Silicon Image and it worked perfectly. Bytecc is a good company, I have many external HD enclosures from them and they've all worked wonders.

I checked this Bytecc one out earlier, but dismissed it because it didn't list compatibility with OSX. I guess I should have given it a second look. When you got it, did you check for compatibility beforehand? I suppose I shouldn't have worried so much, but since it took the time to list compatible systems and didn't include OSX, I figured why risk it.
I ended up going for the Rosewill. I have some of their equipment and have nothing but positive things to say about them. My only caveat is that the Rosewill doesn't appear to be Raid 0 or 1 compatible... However I doubt I would ever want to use RAID on my laptop.

 

[CanadaRAM]

I had a similar question a month or so ago when getting an external. However, the research I did didn't quite agree with what you've quoted. I found that--at least in the technical specs for the enclosure and HDD--eSATA connections did not vary in speed depending on whether there was a FW or USB with it.

i.e. the data transfer rates of the eSATA connection for drives that had only eSATA and drives that had both eSATA and FW were both quoted at 3.0 Gbps.

You understand that those specs you have read are the theoretical specs of the SATA connection for the drive, and not a measure of actual performance of the enclosure as a whole? It's like a 160 MPH speedometer in a Volkswagen Beetle... theoretical, not real world.

Don't trust specs.

 

[maberga29]

You understand that those specs you have read are the theoretical specs of the SATA connection for the drive, and not a measure of actual performance of the enclosure as a whole? It's like a 160 MPH speedometer in a Volkswagen Beetle... theoretical, not real world.

Don't trust specs.

I'd tend to agree with you, and one would hope they would list in the specs a theoretical drop (if one exists) if they sent it through a bus first when including the FW or USB. Don't trust the specs? What else do you have to go on?

A point of comparison; I've had no problem reaching 300MB/s+ transfer rates via eSATA. That's ~2.5Gbps and completely fine with me, especially when the closest alternative of FW800 is less than 1/3 of that (theoretically).

So to me, it doesn't matter so much if I get 2.5Gbps vs. the theoretical max... It's just one hell of a lot faster than anything else.

 

[BrittQ]

This is what MacGurus had to say,

"Not anything current....I don't believe I took any screen shots at the time the testing. The performance of the triple combo bridges was bad enough that I didn't feel it important to preserve the raw data. Pretty pathetic really.

I can tell you FW800, the best of the buses in hard drive data transfers, will restrict 20% of the performance of todays drives over what we see connected via direct SATA. And that will only get worse as drives get faster. Todays SATA drives are easily over 100 MB/sec for many of the newer models, even the very best pure FW800 bridge will keep your performance to under 80 MB/sec."

 

[admiraldennis]

eSATA > FW800 > FW400 > USB 2.

USB works for big transfers but the CPU overhead blows.

A point of comparison; I've had no problem reaching 300MB/s+ transfer rates via eSATA. That's ~2.5Gbps and completely fine with me, especially when the closest alternative of FW800 is less than 1/3 of that (theoretically).

Out of curiosity, what device were you pulling 300MB/sec from? Certainly not from a single hard drive.

 

[BrittQ]

eSATA > FW800 > FW400 > USB 2.

Of course.

But, is an external hard drive with only an eSATA connection > external hard drive with eSata + USB/Firewire? - Everything else being equal, and both connected via eSATA

 

[maberga29]

Out of curiosity, what device were you pulling 300MB/sec from? Certainly not from a single hard drive.

Too true. I was into a RAID0 server at work. I didn't even think about what it was plugged into, just was amazed at the transfer rate (and got the thought of trying it on MBP external). Should have thought that one through a little more.

 

[tmoney468]

I checked this Bytecc one out earlier, but dismissed it because it didn't list compatibility with OSX. I guess I should have given it a second look. When you got it, did you check for compatibility beforehand? I suppose I shouldn't have worried so much, but since it took the time to list compatible systems and didn't include OSX, I figured why risk it.
I ended up going for the Rosewill. I have some of their equipment and have nothing but positive things to say about them. My only caveat is that the Rosewill doesn't appear to be Raid 0 or 1 compatible... However I doubt I would ever want to use RAID on my laptop.

It was actually listed on Newegg for quite a while and people said in the comments that it worked perfectly with OS X...and I think even in this forum someone emailed the Bytecc Support to ask about compatibility and they said it did support OS X as well.

BTW, doesn't your Rosewill look a lot like mine? I wouldn't be surprised if it's the very same card, just with a different sticker on it

 

[Megatron]

Is it worth it to get a new external enclosure with firewire 400 to upgrade the one I have with usb 2.0 now? How much faster is it?

I can't seem to find many that are affordable with firewire 800, which would be ideal since I have an 800 port on my mbp.

This would be for a time machine external disk.

 

[aquajet]

IA point of comparison; I've had no problem reaching 300MB/s+ transfer rates via eSATA. That's ~2.5Gbps and completely fine with me, especially when the closest alternative of FW800 is less than 1/3 of that (theoretically).

More than 300MB/s via eSATA? Isn't that more than the theoretical max?

Certainly a single hard drive couldn't approach that type of performance. Which is why I doubt there's any significant real world differences between using a single drive via eSATA or FW800.

 

[aquajet]

Is it worth it to get a new external enclosure with firewire 400 to upgrade the one I have with usb 2.0 now? How much faster is it?

I can't seem to find many that are affordable with firewire 800, which would be ideal since I have an 800 port on my mbp.

This would be for a time machine external disk.

If it's just used for backups, I would say it's not worth moving to a firewire solution.

 

[maberga29]

More than 300MB/s via eSATA? Isn't that more than the theoretical max?

No, theoretical max would be nearly 400MB/s. But like I sadly realised, I can expect nowhere near that much throughput with a single disk.

But, is an external hard drive with only an eSATA connection > external hard drive with eSata + USB/Firewire? - Everything else being equal, and both connected via eSATA

That's the burning question here. Anyone have answers?

 

[BrittQ]

That's the burning question here. Anyone have answers?

I'm really surprised that no one has an answer for this.

 

[Sun Baked]

I'm really surprised that no one has an answer for this.

Does it really matter if it is running at 300 MB/s or slows down to 200MB/s running through a really bad bridge board -- both are still much higher than the mechanical speed of the drives, while FW800 is much closer to that limit.

 

[BrittQ]

I've found some quasi-evidence while reading some enclosure descriptions, to support the idea that having an external hard drive with esata + usb/firewire slows down the esata connection because it bridges the data.

I found a few descriptions stating similar ideas.

"This box is built for speed—data passes straight from drive to SATA host controller with no "bridge chip" to slow the transfer, unlike FireWire and USB enclosures."

 

[tmoney468]

I've found some quasi-evidence while reading some enclosure descriptions, to support the idea that having an external hard drive with esata + usb/firewire slows down the esata connection because it bridges the data.

I found a few descriptions stating similar ideas.

"This box is built for speed—data passes straight from drive to SATA host controller with no "bridge chip" to slow the transfer, unlike FireWire and USB enclosures."

Going along with that quote, it doesn't say "unlike eSATA + Firewire or USB enclosures." It wouldn't make sense for an enclosure that has say eSATA + USB2 to somehow pass the data through the USB chipset and then output it to eSATA. As far as I know, a SATA internal drive sends it's data through the wire inside to the SATA chipset of the enclosure, then through the eSATA wire connecting to your computer. So I don't see how having a USB option would make it any slower if it was soley eSATA.

 

[plumbingandtech]

I can't wait for the day when Mac Book Pros can BOOT eSata.