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mellofello

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Feb 1, 2011
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Im considering getting a external usb 3 or thunderbolt ssd. I would like to move osx and all aplications over there. Will I have problems booting from thunderbolt? Are there any diy guides floating around?
 
Im considering getting a external usb 3 or thunderbolt ssd. I would like to move osx and all aplications over there. Will I have problems booting from thunderbolt? Are there any diy guides floating around?

I'm considering this as well, so I would be interested to hear what people say. I would think Thunderbolt would be a better option for this. The new LaCie rugged drives have USB3 and Thunderbolt and retail for around $200 I believe.
 
Im considering getting a external usb 3 or thunderbolt ssd. I would like to move osx and all aplications over there. Will I have problems booting from thunderbolt? Are there any diy guides floating around?

I'm considering this as well, so I would be interested to hear what people say. I would think Thunderbolt would be a better option for this. The new LaCie rugged drives have USB3 and Thunderbolt and retail for around $200 I believe.

There is a good thread here on this using the Lacie the good Dr. mentioned.

Just attach the drive and clone your existing drive to the TB external using Carbon Copy Cloner. Then option key boot to the external. Go to System Prefs in the Startup Disk pane and select the TB external as the boot disk. Done.
 
Thunderbolt is not needed for single-drive ssd external enclosures as USB3 is more than capable of handling SSD speeds.

Something to keep in mind though is that USB3 uses slightly more CPU-power.
 
i run the os off a external via usb3. its fine, getting 300+- on both read/writes. with a samsung 840.
 
I booted my mid-2010 iMac off of an SSD via FireWire 800. Even though FW800 is a bottleneck when it comes to raw sequential transfer speed, the random access speed still makes it much faster than the internal HDD. Using USB 3.0 or Thunderbolt will make an external SSD very close to an internal SSD in speed.
 
Thunderbolt is not needed for single-drive ssd external enclosures as USB3 is more than capable of handling SSD speeds

Not entirely true. USB3.0 uses considerable more CPU than Thunderbolt.
 
There is a good thread here on this using the Lacie the good Dr. mentioned.

Just attach the drive and clone your existing drive to the TB external using Carbon Copy Cloner. Then option key boot to the external. Go to System Prefs in the Startup Disk pane and select the TB external as the boot disk. Done.

Sorry, but what's the advantage of having OSX in the external drive vs the internal drive. I could see that for bootcamp windows, but why native OSX?

Nevermind. I got my answer from the link above.
 
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Not entirely true. USB3.0 uses considerable more CPU than Thunderbolt.

First off, in the part you quoted there is nothing that isn't true. USB3 IS more than capable of handling SSD speeds, thus Thunderbolt is not needed.

Secondly, and lastly, I already wrote that USB3 uses more CPU, did you read my entire post?
 
Don't let others dissaude you from putting together a USB3 SSD boot drive.

It's easy, cheap, and MUCH faster than you would be led to believe.

IMPORTANT:
You want to get a USB3 enclosure (or USB3/SATA dock) that has either an
ASMedia 1051e controller chip
or an
ASMedia 1053 controller chip.

Either of these will give you UASP support (USB Attached SCSI Protocol) for faster performance on UASP capable systems.

I'm using a plugable.com "lay-flat" dock with an Intel 520 series SSD.

I'm getting writes @184mbps and reads @381mbps. Not bad at all.

Your boot times WILL be slightly slower than you would get from an internally-mounted drive -- but still quite fast. Once up and running, I doubt you'll perceive any difference from an internally-mounted drive in normal usage.
 
I've set up an external SSD with thunderbolt and made a custom fusion drive with the internal HDD. No problems.
 
First off, in the part you quoted there is nothing that isn't true. USB3 IS more than capable of handling SSD speeds, thus Thunderbolt is not needed.

Secondly, and lastly, I already wrote that USB3 uses more CPU, did you read my entire post?

Test here to prove it.

I wish they had shown CPU utilization during these tests though.
 
I thought TB didn't allow yet to use external drives as the boot drive. I read it somewhere. USB 3 can use an external drive as boot up drive.

Does anyone use an external SSD TB drive as boot up drive for sure?
 
I thought TB didn't allow yet to use external drives as the boot drive. I read it somewhere. USB 3 can use an external drive as boot up drive.

Does anyone use an external SSD TB drive as boot up drive for sure?

Look a few posts above. I linked to a thread where several folks are doing this and it works fine.
 
I thought TB didn't allow yet to use external drives as the boot drive. I read it somewhere. USB 3 can use an external drive as boot up drive.

Does anyone use an external SSD TB drive as boot up drive for sure?

For sure I do and it works no problem, I use a lacie rugged ssd thunderbolt.
 
I booted my mid-2010 iMac off of an SSD via FireWire 800. Even though FW800 is a bottleneck when it comes to raw sequential transfer speed, the random access speed still makes it much faster than the internal HDD.

+1 for FW800 and SSD. I have a mid-2011 27" iMac (I figured I would wait it out for BYOD ThunderBolt enclosures - oh, boy! :rolleyes:) and it is WAY snappier with the system on FW800 than using the internal 7200 RPM 3.5" WD disk. Also, the CPU usage while the disk is being pounded is next to nil.

By the way I have used the Mac OS X install DVDs to copy my system partitions a few times (not requiring tools like Carbon Copy Cloner). Worked fine.
 
I have an alternate boot Samsung 840 pro in a WD Mybook TB enclosure. Fast, but not as fast as the internal SSD's, but generally works fine.
 
I have an alternate boot Samsung 840 pro in a WD Mybook TB enclosure. Fast, but not as fast as the internal SSD's, but generally works fine.

do you think Thunderbolt drive would be as fast as internal SSD?
 
do you think Thunderbolt drive would be as fast as internal SSD?

I have done many tests and found the fastest is the Fusion drive (SSD portion), then the 768 SSD internal, then a bit slower is the TB Samsung 840 Pro SSD. Interesting since the samsung is probably a faster ssd than what is going inside the imac. So I conclude that there is some added latency from the TB interface. Not a huge drop but measurable. I didn't save my bench runs but I can say that in the real world, I wouldn't worry about the small differences. All three ways are very much faster than a 7200 standard drive. I was surprised that the Fusion clocked in at the top, above the 768ssd, but I would expect again in real world the Fusion drive would slow down once the hard disk came into play. USB3 enclosures are noticeably slower than the TB ones to me. TB enclosures are expensive, but if you are talking about SSD's I wouldn't cheap out here.
 
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Im considering getting a external usb 3 or thunderbolt ssd. I would like to move osx and all aplications over there. Will I have problems booting from thunderbolt? Are there any diy guides floating around?

Can I ask... what kind of computer do you have?
 
I have done many tests and found the fastest is the Fusion drive (SSD portion), then the 768 SSD internal, then a bit slower is the TB Samsung 840 Pro SSD. Interesting since the samsung is probably a faster ssd than what is going inside the imac. So I conclude that there is some added latency from the TB interface. Not a huge drop but measurable. I didn't save my bench runs but I can say that in the real world, I wouldn't worry about the small differences. All three ways are very much faster than a 7200 standard drive. I was surprised that the Fusion clocked in at the top, above the 768ssd, but I would expect again in real world the Fusion drive would slow down once the hard disk came into play. USB3 enclosures are noticeably slower than the TB ones to me. TB enclosures are expensive, but if you are talking about SSD's I wouldn't cheap out here.

Were you measuring bandwidth (MB/s) or IOPS/latency? For SSDs, bandwidth is nearly irrelevant... but often still in use because that is the way HDDs were measured. Enterprise customers are more sophisticated.

/Jim
 
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