USB3 as main drive makes finder non responsive

Replace the internal hard drive again. USB 2.0 is too slow anyways.

Or, boot from Firewire (800), that's much faster than USB.

and I will add buy a more reliable drive. If I were in you I would go for a SSD internal that are faster and more reliable of the traditional HDD

P01550n said:

Thanks for your suggestions guys, but my goal is not spending any more money for this computer and therefore making this damn usb drive work.
I dont care if it is slow. I would just like not being forced to reboot to make the drive responsive again.
But maybe its a problem with USB ? I dont understand why the mac is unable to wake the drive !

Click to expand...

Because USB2 is 13 years old now and is generally buggy when used for anything other than general peripherals. I'm guessing that using it as a system drive is just too taxing with constant reading and writing. I used to have a external Seagate drive that was unable to transfer large amounts (300GB+) in one go because it would just freeze and disappear from the PC until I unplugged it and plugged it back in.

mikeorchard said:

Because USB2 is 13 years old now and is generally buggy when used for anything other than general peripherals. I'm guessing that using it as a system drive is just too taxing with constant reading and writing. I used to have a external Seagate drive that was unable to transfer large amounts (300GB+) in one go because it would just freeze and disappear from the PC until I unplugged it and plugged it back in.

Click to expand...

I've never had any problems. Copying about 1TB from one external USB 2.0 drive to another, both connected to a mid 2010 MacBook Pro, no problems at all.

The problem seems to be with the hard drive, if it goes to sleep and doesn't wake up. Could be possible to change something in System Preferences in the Energy saving settings to avoid the hard drive being powered down.

mikeorchard said:

Because USB2 is 13 years old now and is generally buggy when used for anything other than general peripherals. I'm guessing that using it as a system drive is just too taxing with constant reading and writing. I used to have a external Seagate drive that was unable to transfer large amounts (300GB+) in one go because it would just freeze and disappear from the PC until I unplugged it and plugged it back in.

Click to expand...

Nonsense, USB 3 is less reliable and buggier than USB 2, you won't hear many complaints with USB 2 yet with 3 there are plenty of cases.

Example, just search here on MR, people trying to install ML on an external USB 3 device end up with an unbootable system, USB 2 no problem.

gnasher729 said:

I've never had any problems. Copying about 1TB from one external USB 2.0 drive to another, both connected to a mid 2010 MacBook Pro, no problems at all.

The problem seems to be with the hard drive, if it goes to sleep and doesn't wake up. Could be possible to change something in System Preferences in the Energy saving settings to avoid the hard drive being powered down.

Click to expand...

One external drive to another is not the scenario I described. It could be that the problem was also with my drive and not USB2 but again it's hard to know.

justperry said:

Nonsense, USB 3 is less reliable and buggier than USB 2, you won't hear many complaints with USB 2 yet with 3 there are plenty of cases.

Example, just search here on MR, people trying to install ML on an external USB 3 device end up with an unbootable system, USB 2 no problem.

Click to expand...

Equally I could say your statements are nonsense since I haven't had a single problem with my USB3 external drive and have with a few USB2 ones over the past decade.

I just searched for 'ML on USB2' and got 16 results, mostly not about using it as a system drive and 'ML on USB3' and got 54 results, again mostly not about using it as a system drive. So it's hard to verify what you're saying. Searching for 'boot from USB2' got 414 results and 'boot from USB3' got 212.

The fact remains that USB2 is only capable of 35Mb/s, which considering internal hard drives are around 80-90Mb/s and SSDs even faster, just isn't an ideal way of booting an OS if you're using the computer on a daily basis.

To the OP, have you changed the Energy Saver settings in System Preferences?

mikeorchard said:

Equally I could say your statements are nonsense since I haven't had a single problem with my USB3 external drive and have with a few USB2 ones over the past decade.

I just searched for 'ML on USB2' and got 16 results, mostly not about using it as a system drive and 'ML on USB3' and got 54 results, again mostly not about using it as a system drive. So it's hard to verify what you're saying. Searching for 'boot from USB2' got 414 results and 'boot from USB3' got 212.

The fact remains that USB2 is only capable of 35Mb/s, which considering internal hard drives are around 80-90Mb/s and SSDs even faster, just isn't an ideal way of booting an OS if you're using the computer on a daily basis.

To the OP, have you changed the Energy Saver settings in System Preferences?

Click to expand...

Does USB 2 have interference?
Do you think a 13 year standard is not more stable than a fairly new USB 3 standard?

Just a few (USB 3 interference) links.

Using USB 3 devices on Mac computers FAQ

USB 3 interference Google search, About 5,050,000 results.

pull the plug and put the drive inside or get a new iMac, USB 2 is a fine standard, but it's so slow... you are probably getting 25 r/w and thats just too narrow a pipe to run your OS on.

I get it that you don't want to spend more money, and I get it that making the drive you have work is an interesting challenge.

But if you were willing to buy a bare FW800 enclosure (there are many out there) and also were willing to pull apart your USB3 drive (I assume you're talking about a drive that you bought as a housing+drive unit), then you could drop the drive into the FW800 enclosure and it's really highly likely that your problems will go away.

Otherwise -- is there any chance you could borrow a USB3 drive made by another manufacturer, and try it? If I were you, I'd want to exclude the possibility that the sleep/spin-down implementation on the drive you have is faulty.

That's a possibility, because I had the reverse situation on a FW800 drive that would not sleep. The manufacturer agreed it was a bug and said it was in the Oxford chipset, which handled sleep/wake properly with Windows but not with OS X.

If the drive is timing out and going to sleep, you can install a little applet called "Keep Drive Spinning". I use this on an external FW800 drive that I keep my Aperture masters on. It would spin down (some drives' firmware overrides the System Preferences settings) and when I launched Aperture it would take quite a while to spin back up. I also use it to keep a drive attached to my Time Capsule spinning - my son has his iTunes library on there instead of on my MBA's SSD. If the drive isn't spinning and mounted on the network and connected, when you start up iTunes it wouldn't see it and it would create a new Library in the default location.

Here is a link:

http://www.macupdate.com/app/mac/31158/keep-drive-spinning

justperry said:

Does USB 2 have interference?
Do you think a 13 year standard is not more stable than a fairly new USB 3 standard?

Just a few (USB 3 interference) links.

Using USB 3 devices on Mac computers FAQ

USB 3 interference Google search, About 5,050,000 results.

Click to expand...

Yes, USB2 does have interference. Age =/= stability. Do you have any understanding of electronics and electricity? Search for USB2 interference on Google and you'll get 4.8 million hits...

mikeorchard said:

Yes, USB2 does have interference. Age =/= stability. Do you have any understanding of electronics and electricity? Search for USB2 interference on Google and you'll get 4.8 million hits...

Click to expand...

The first link concerning interference when I did your suggested USB2 interference search was this:
Using USB 3 devices on Mac computers FAQ

Most others were anti interference cable's, I don't see any link which says it's a big problem while I did find two of my above links (concerning USB 3) when searching for USB 2 interference on the first and second page!

FYI, yes, I did study electronics.

But, whatever, old drivers are more stable than new ones, if you don't see this then that's not my problem.

I am gone.

P01550n said:

Hi guys,

My late 2006 iMac internal hard drive has failed again. And since it's such a pain in the *** to open the case and replace the HD i have decided to boot from a usb3 external drive.
It's certainly much slower but it works.

My problem is that after a while (1/2hours, hours, its unpredictable) the drive seems to stop being readable and everything on the mac needing to read from the hd becomes unresponsive. Finder in the first place.

I have tried unplugging then replugging the external HD with no success.

It's like the mac would tell the hd to sleep at some point but the later would never wake.

Someone has an idea?

Thanks for your help !!

Click to expand...

is the drive bus powered or external powered... the usb2.0 vs 3.0 debate is moot since the 2006 iMac has no 3.0 ports... i had some issues with a bus powered CD drive that the USB cable had 2 plugs 1 for data and power and 1 for just power... the drive would crash randomly when and not recognize the disc when you installed a new disc if just the data usb plugged in... with both plugged in the drive worked fine... since then i do not trust USB powered drives... if this drive is bus powered maybe try an externally powered usb enclosure... and as others have said try a FW enclosure... even FW 400 will be faster than 2.0 in real world terms...

P01550n said:

My problem is that after a while (1/2hours, hours, its unpredictable) the drive seems to stop being readable and everything on the mac needing to read from the hd becomes unresponsive. Finder in the first place.

Click to expand...

Are you saying that while you're actively using the computer the drive will just become unreadable? Does the Mac report that the drive was ejected?

As an add-on to what others have already said, a FW800 connection will work much better than USB 2.0. I'm using an SSD through FW800 and it works great.

The firmware in many, not all, external drives USB2.0 or USB3.0 is written to put the drives to sleep after a period of non-access. Many of the inexpensive drives will not communicate with the OS to the point where your settings in the Energy Saver Preference Pane to not put drives to sleep will not reach the external drive. When the drive goes to sleep, it may not wake.

I've had this problem with a few inexpensive USB3.0 brand externals. I'm still looking for one that will abide by the Preference settings to not allow sleep, because even when they do awake when they're supposed to, there's a delay before the read/write takes place. For backups, this is fine. For an OS drive or working scratch disk, it's not acceptable.

The Western Digital USB 2.0 external drives I use do keep spinning until I sleep the computer or shut down.

macthefork said:

The firmware in many, not all, external drives USB2.0 or USB3.0 is written to put the drives to sleep after a period of non-access. Many of the inexpensive drives will not communicate with the OS to the point where your settings in the Energy Saver Preference Pane to not put drives to sleep will not reach the external drive. When the drive goes to sleep, it may not wake.

Click to expand...

Which is why Keep Drive Spinning is a great little applet...