The USB 2.0 spec allows up to 0.5A for a high-power device. USB 3.0 allows up to 0.9A. USB-C allows up to 1.5A. Any additional power requires implementation of either the battery charging spec (which, I believe, can’t be used simultaneously with moving data) or the power delivery spec over USB-C.
In other words, the T5 may be able to draw the power it requires from a USB 3 port (0.8A is less than 0.9A), but the T7 may not be able to get what it needs unless it is plugged in to a USB-C port.
A 2014 Mac mini doesn’t have any USB-C ports, so there may be problems if the driver requires more than 0.9A of current.
The strange thing is that the drive seems to work OK as long as you’re not booting it. The only explanation I can think of is that Apple’s USB-A ports have a proprietary high-power mode (used for the SuperDrive), which might also be able to power the T7. But that power mode may not be available before macOS starts running.
But the fact that the drive appears as a boot device when you hold down option, seems to indicate that this isn’t the case either.
It’s definitely worth trying a powered hub, if you have one. My Mac (2018 mini) has an Anker 10-port hub which is used for many devices, including my backup drives. I can boot from these drives, but that doesn’t mean anything because these drives have their own AC power supplies.
If the drive shows up properly in the boot loader, the drive is getting enough power. Or rather I should say, if it can show up its volume in the boot loader, the power it’s receiving is sufficient for the Mac to continue to boot from it.
I would be very interested in hearing what the PRAM reset does.
I do…but it’s in use on my iMac… ut I think I will /or tow it long enough to see if the power draw is the problem…if it is and the performance increase is worth it I can spring for another one. Or…since it’s file server performance is fine and it’s only the remote management slowness I might blow it off as not worth it…but y least I would know the answer then.
Nothing…as did the cable swap. I did notice that on some option boots the T7 shows up in option boot with the volume name and sometimes it shows up as efi_boot…and that didn’t start until after the PRAM resets.
I had edited my precious post to say that on the Discourse page but wasn’t sure if the edits would get sent to the list…apparently it didn’t.
AFAIK the boot process is very energy intensive. Both for the computer and the bootdrive/SSD. Massive reads/writes and checking of correctness. And in my experience the boot process falls back onto booting from the internal drive if anything on the chosen bootdrive fails any of the tests. A low power situation will probably result in switching to the internal drive for booting. That the T7 shows up as a bootable drive is logical, it gets only read and checked if there is a valid system on the disk. Reading is not very energy intensive. Too bad the docs from Samsung don’t state the needed energy for reading, writing and booting from their SSDs.
It’s definitely worth trying a powered hub
Given the specs Shamino has given make that a powered USB-C hub. I have only a powered USB3 hub and doubt if a T7 gets enough juice from that.
When you select the T7 in the boot loader, does it start to boot from it and then after a while fall back to the internal, or does it start booting from the internal right away?
Also, if the working theory is just that the T7 is exceeding the peak power draw of USB-A on the Mac mini, do you have a powered USB-C hub you could play with? Would be interesting to hook up the T7 to it (via A-C dongle if you don’t have a C cable) and see it that changes anything. A proper C port on a powered hub should be able to deliver 15 W which is 3 Amps at A voltage levels, so more than enough to power the T7.
Can you connect a USB-C hub to a Mac without USB-C ports? A 2014 mini has type-A ports and TB2.
Still, I would find it surprising if a USB-A port can’t power the device at all. Samsung’s product page says (if you scroll down to the Multi-device compatibility section) that “T7 is compatible with USB 3.0 and USB 2.0”. Which tells me that even a USB 2.0 port should be able to supply enough power.
Unfortunately, it may simply be that the T7 isn’t bootable on this Mac. We know that, for instance many WD MyPassport drives can’t boot Catalina. Maybe it is due to power issues. Maybe something else. It’s hard to tell without diagnostic tools that are probably not available outside of Samsung’s own labs.
Those MyPassport drives have hardware disk encryption and those drives can’t be used in another case if the USB board goes bad so it’s not surprising they have issues booting as well.
Since I have a Samsung 500gb T7 not being utilized at the moment, I decided to clone my main Catalina startup volume to it to see if it would boot like the T5 models do without issue. I have a 2012 Mac Mini 2.3 GHz i7 Quad Core. It boots fine from the T7 directly connected to the computer port and also from a USB 3 hub (Insignia). So for me, no power issues here. I am selecting the boot disk from the Startup Disk preferences pane.
Now, I know the OP was trying to boot Monterey which I can’t do since Catalina is as far as I can go with a 2012 Mini but at least with my computer, there are no issues booting from a T7 (or a T5).
It seems like thee is a delay and the drive light flashes off and on showing access…and the logo and progress bar appear normal sized for 15 or 20 seconds…then after a bit the logo and progress bar blink off and back on larger (like it appears on a smaller monitor) followed by about 3 or 4 seconds of progress bar and then the users on the login page appear.
I have one thing you can try if everything else fails. This is how I do it when working with deployment testing.
Boot up with internal.
In Disk Utility, Format the disk with MS DOS FAT
Quit Disk Utility and start it again.
Format the disk with MacOS Extended. (Not APFS)
Start the installer from /Applications on internal disk.
Choose “Show All Disks…” Choose the external disk.
The installer will now format the external disk to APFS and make sure it has the right boot disk layout, which in the past has made a difference several times for me. There might also be some other apple magic going on. Tested this just now with Samsung T5 and Mac mini late 2014. This is with Monterey 12.2 which came yesterday.
Thanks for testing, good to know both situations work.
The T7 comes in three sizes, 500 GB, 1 TB and 2 TB. Probably Samsung leaves all other components the same on all three models and adds only extra memory. Most likely extra memory chips require more power.
I read this thread back to see if Neil mentioned the size of the T7, but found nothing. But as he uses it to backup multiple MacBooks it’s likely larger than 500 GB.
What also is a possibility to get info on the power needed is going to System Info (About this mac/ System info/Hardware/USB) while the T7 is connected to the mini. (Wording will differ, different language and different System.) It will give a top-down view off the USB hubs and attached disks, including “Power available” and “Power needed”.
On a sidenote, when I oriented on buying the 2014 mini (back in 2016) I’ve read a number of reviews. One remark I noted said: “The 2014 mini has 5 USB-ports and the earlier mini’s have 4.” It might be that Apple maxed out the available power to feed the fifth USB port. According to MacTracker the 2012 and the 2014 mini have the same form factor and weigh almost the same. So probably the same power supply.
It still is possible that it’s a power problem, but Shamino’s suggestion that the T7 is not bootable is also still valid.
As an alternative option (reading the specs in MacTracker) a Thunderbolt to USB-C connection could be a solution (if the T-bolt port is still unused).
I checked out the power requirements and here is what I found. First, using my Toshiba XS700 240gb as the boot drive plugged directly into the computer:
Ok, I did a little more testing today. The T7 is the 2TB mode and likely takes a bit more power than the smaller ones. My conclusion after my testing is that there’s some strange incompatibility with booting that model drive on at least this particular late 2013 mini. I did see the recommendation to reformat the drive as FAT and then reinstall again…and I might end up doing that. However…I’ve already copied over the 700 GB of CCC TM clones folders to it so would have to copy them back to a spinning drive and back to the T7 afterwards and I’m tired of mucking with this for today at least…if I get bored I might try that again although I did that already…the drive came as FAT and I nuked it to a single GUID/APFS volume before doing anything. I’ve reinstalled Monterey to the T7 3 (or maybe 4, can’t remember) times with both a single APFS container for the boot volume and another APFS container for the shares as well as a single APFS container with just a single partition…so I’m not thinking that will do anything for me unless nuking it back to FAT again causes some change…but when I get bored I’ll try it again.
Here’s the results of my additional testing today.
Booting from the internal drive with the internal drive selected as startup and the T7 attached. About 0:55 with the small logo and progress bar then total of 1:03 with the larger logo/bar to the login screen. No T7 drive light flashing
Booting with the T7 selected as startup. Same indications as before but about 1:26 for the small logo portion and 1:36 total with the larger logo to the login screen. There was very brief intermittent drive activity light on the T7 about 10 and 40 seconds into the first 0:55 with none during the last part to the login screen.
Option boot with the T7 selected then immediately selecting refi_boot and return when that screen appeared. About 0:10 to the option boot selection screen, 1:24 with the small logo and 1:36 to the login screen. No flashing light on the T7 but the light was on.
Shut down my iMac to borrow the powered USB A 3.0 hub, hooked that to the mini and the T7 and keyboard/mouse to the hub. Same dual size logo routine and 1:37 with the small logo and 1:43 to the login screen. This one was slightly different as the screen stayed black for about 30 seconds after the bong then about 2 seconds of T7 drive light activity before the small logo portion…but no drive light activity after that.
I also did some more googling and saw several reports that said their 2013 mini was booting just fine from a T7 although the size wasn’t specified…as well as reports that said it never worked and some that said it worked some of the time but not reliably. So…apparently there’s some weird issue going on at least between this model and the T7 for some people…and frankly I’ve probably wasted waaaay too much time on it already…but after hearing and reading about how it worked for some my stubborn gene kicked in. As I said earlier in the thread…the network performance to the T7 from the laptops that CCC backs up to it works fine and about 10x as fast as the Seagate Backup+ drive those shares used to be on so I’m not really losing anything there. It’s just the performance of macOS on boot time, app load time, etc that I would have liked to improve…especially as the internal spinning drive is now 8+ years old…but other than mucking around with it this week I only use Screens to remote in and manage the thing maybe once a month or whenever CCC tells me the job failed and in the past that was usually because the Seagate drive dismounted itself. I solved that issue by setting up both Keep It Spinning on the mini as well as a CCC job on the mini which copied a small text file from the internal drive to the Seagate once a day…not sure which of those actually fixed the dismounting issue since it was 6 or 8 months back when I did it.
If/when I try reformatting the SSD I’ll report back on success or failure but otherwise unless somebody has another idea I’ll just live with it.
Did you check in your system report what values for power are there similar to what I posted before your post? That might give you some idea of what is required. Also, maybe this is a Monterey issue of some kind.
Didn’t see your post before but just checked and for the T7 it says 900 mA available and 896 required…
That’s pretty close to being more needed than available strictly on the numbers but if the ‘required’ number is anything like what vendors typically say is required for a computer or drive there is almost certainly some buffer in the ‘required’ number over what is actually needed. However…since using a powered hub didn’t help either I’m thinking it’s not a power issue but something else…especially given the all over the map reports that google found for me. All of them were anecdotal but at least from semi-reputable forums and websites.
It could even be something strange since the T7 runs USB 3.2 and the mini is only 3.0…or could be something strange with the USB C to USB A cable that come with the T7. I’ve got a plain C to A adapter plug so I’ll give that a try with a C to C cable on the drive…although I don’t really expect that to change anything.
The power numbers are the same for my T5 and T7 like the ones you mentioned. Both boot Catalina fine on my 2012 Mini. I see the same numbers for a WD easystore which also boots fine. So maybe it is something unique to the newer Mini or it’s a Monterey issue which I can’t run otherwise I would have tried that to see what happens.
You said you’re connected to a Sony tv. Maybe try a regular monitor just to see if that somehow is causing the issue although that doesn’t seem likely.
You know, in your case my gut feeling also says it’s related to macOS and that specific mini rather than the hardware. Perhaps there could be something wonky with the T7’s bridge circuitry, but my money really wouldn’t be on the hardware, especially the cable.
But that said, I’ve become increasingly weary of cable issues. Not long ago I went through a massively odd ordeal trying to get a simple USB-C connection to work using the manufacturer’s included cable, which was neither faulty nor flimsy, and definitely not cheap, and I just couldn’t get things to work. Tried many other quality USB-C cables and nothing worked out. Finally, in an act of despair I tried Apple’s expensive 80-cm TB3 cable and low and behold that did the trick, all oddness went away. NB, this was a USB connection, not TB. And ever since I’ve felt that when you have a kind of odd issue with connecting hardware, especially over USB with all its complicated variants and overly confusing spec terminology, you can’t really try enough cable alternatives and variations. Of course this is assuming you’re curious to truly wrestle this issue to the ground. Otherwise, it’s likely mostly a waste of time. ;)
