I installed a "Highpoint RU1022AM RocketU Dual port USB 3.0 for Mac OS" PCI-e card in my Mac Pro/10.6.8. I connected a Hitachi Tuoro 4Tb external hard drive and a Samsung 1Tb drive in an IcyBox USB 3.0 enclosure. The drives are mounting and working, but I have some questions:

1. I timed the Hitachi drive and it copied 1Gb of data in 15 seconds. (Because I failed maths) Can anyone tell me if this is indeed 10 times faster than USB 2? Am I getting anything near 5 Gbit/sec?

2. I cloned my startup drive to the Hitachi. System Preferences/Startup Disk sees the drive, but I am unable to boot from it. Is there something I can do? Or is it not possible to boot from a PCI-e card? It's not a worry, frankly.

3. The Mac Pro will no longer sleep. This is more worrisome. I have installed the latest driver for the expansion card. I have reset the PRAM a number of times. I have run OnyX to delete system caches.

When I click on Sleep, the fans ramp up as usual and the screen blanks, as usual. But, where the fans used to quickly stop, the power button would start slowly flashing and the Mac go to sleep, NOW the fans never stop spinning and the Mac will not sleep. I can hit the space bar and the screen comes back to life, but I have to reboot before it starts behaving normally again.

If I boot into Single-user Mode, I get "tried 3 times, failing" (I paraphrase) and have to use the startup button to force quit. If I boot from another drive, Disk Utilities says everything looks fine.

If I don't put the Mac to sleep, everything works fine.That's all I can think of for now.

Interestingly, the USB 3 drives show up in the Finder as internal, rather than external, hard drives.

Thanks in advance for any replies.

Oh, yeah. There is a power plug on the USB 3 card. Would it help to boot from the card if I plugged that into something?

Cheers.

I cannot answer all your questions, so I'll pick at some in the hope others can add.

- By the numbers you provide those data moved on average at 1/15 GB per second, that's around 60-70MBps, or close to the max throughput of USB-2. That said, that data rate must perforce be close to the sustained data rate, which tends to be considerably lower than the max, and is also dependent on the type of data (large vs. small files etc.). You wouldn't be able to get that data rate with 'regular' USB-2, so it's safe to say you see the presence of USB-3 in that number.

- Mac OS X provides USB-3 support in 10.7.4 and 10.8 for certain Macs, but 3rd party peripheral vendors may extend the hardware/OS options. Off the top of my head I don't know about Mac OS X support for booting with USB-3 even though it is backward compatible with USB-2, but there could very well be an issue there, particularly since you're running Snowy.

- The problems with sleeping appear to be at least twofold (no sleep, and reboot issue). It's possible that the driver is polling the bus excessively or something along these lines, and in the process prevents sleeping. But frankly, your other observations suggest there's more going on. The requirement to reboot to get things back on track and the Single User Mode behavior you describe point to a 'real' problem, which is likely driver and/or (USB) hardware related. Whether that's the card or the peripheral(s) I can't say for sure, but my bet's on the card.

For the sleep and fan issue, I have two thoughts:

Have you opened the computer and checked for dust accumulation? That could cause heat buildup, thus making the fans go at high speed and interfering with sleep.

My Mac Pro had a sleep problem, albeit a bit different. It would sleep but then refuse to wake, not all the time but enough to cause concern. I got a blinking power light (about once a second) and the only thing that I could do was to force a shutdown by holding the power button. Resetting PRAM did not cure it.

I replaced the internal backup battery a few weeks ago, and the problem has not reappeared. That may be coincidence, but that's what happened.

In order to be able to boot from a PCI card, the card has to have a ROM that contains OS X drivers. If the card comes with software drivers, you can't boot from it...because the computer doesn't know how to talk to the card until the drivers are loaded, and the drivers aren't loaded until OS X boots.

smc/smu/pmu problems related to battery, and hardware drivers are the big two that interfere with sleep. More often it's drivers. See if safe boot can go to sleep on its own. Check console's logs for indications of cause.

Thank you all for your advice/explanations. I have discovered the manufacturer's website and found that they know there is a Mac sleep problem. They are writing drivers to correct the problem, but nothing since April.

Also, I find by watching Activity Monitor the speed of the USB3 drives is only twice as fast as a USB2 drive copying the same material.

Once I've got all my data shifted around to my liking, I think I'll remove the USB3 card until new drivers are released. The new USB3 drives can still be plugged into USB2 sockets.

John: I gave the insides a good blow out when I installed the card and the Mac's only 16 months old.

Virtual1: The Mac refused to boot into Safe Mode, the progress bar stalling a third of the way. I had to force quit.

USB 3 is, at least in theory, 10 times faster than USB 2, but any system is only as fast as the slowest part. Normal mechanical hard drives can't get to USB 3 speeds; no matter how fast the interface is, you're limited by the speed of the rotating platter and how fast the heads can move from place to place.

Try a verbose boot and see if it produces a useful error message. Sounds like it was running fsck and stalling. Very likely disk io errors.

Try booting off another OS such as attached ext hdd or computer in firewire target mode to see if the hardware is ok.

Try booting it in fw target mode and cable to another mac to check the hdd with disk utility.

Thanks! I'll get back to you...

I have removed the USB 3 card and now I am sleeping fine.

I'll connect the two USB 3 drives I bought to USB 2 until HighPoint gets around to writing new drivers for the card.

Thanks all for the help.