Time Machine Backup External Hard Drives for on old Mac Pro 3.1o

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Level 1

13 points

Time Machine Backup External Hard Drives for on old Mac Pro 3.1o

Hello

I have an old Mac Pro 3.1 which I use for music making on Logic Pro 9.1.8. The OS is 10.8.5

This old system work for me, although it had been in storage for a while up to now. Starting it up today, first time for over a year, it crashed. It then started back up and seems to be working well.

BUT I really need to have a proper back up regime as old hard drives can die.

I have TWO hard drives installed in the Mac Pro 3.1, specs being:

Macintosh HD

Kind: Volume

Created: 18th Dec 2007

Version: 10.8.5

Format: Mac OS Extended (Journaled)

Capacity: 319.21 GB

Available: 82.19

Used: 237,021,999,104 bytes (237.02 on disk)

Audio (the second hard drive, to separate Logic Pro projects from system stuff)

Kind: Volume

Created: Monday 4th Feb 2008

Format: Mac OS Extended

Capacity: 749.81 GB

Available: 82.19 GB

Used: 321,377,779,712 bytes (321.38 on disk).

I have a SanDisk Prof G-Drive ArmourATD 5TB that I use for Time Machine backups with my much newer MacAir. This external hard drive only had USB-C connections. But I like this brand, it was good reviews and hasn't let me down at all.

When I connected it to my Mac Pro 3.1 with a USB adapter a message popped up saying "The disk you inserted was not readable by this computer". I wasn't going to use it to backup the Mac Pro 3.1, but I wanted to see if it recognised it. It did give an option to "initialise". I don't know if this was because I hadn't set Time Machine up on the Mac Pro 3.1 (can't really until I have an external hard drive to use for it), or whether the SanDisk Prof G-Drive ArmourATD is not compatible for the old Mac Pro 3.1 (or maybe the adapted was faulty).

So my question is: can I use two different SanDisk Prof G-Drive ArmourATD hard drives, with the relevant USB adapter, to create Time Machine backups for the two hard drives installed in my old Mac Pro 3.1 please? I would need to buy a couple of them, with capacities fitting for these (now small) old hard drives but I consider that to be a good investment. As I say, I like this brand, but I don't want to spend my money on something that won't work, hence my question.

If these are NOT compatible, can anyone tell me what hard drives I should used please?

Further specs for the Mac Pro 3.1 are below, just in case you need to know to answer my question:

From System Profiler

Hardware Overview

Model Identifier: MacPro 3,1

Processor name: Quad-Core Intel Xeon

Processor Speed: 3.2GHz

Total Number of Cores: 8

L2 Cache (per processor): 12MB

Memory: 4GB

Bus Speed: 1.6GHz

Boot ROM version: MP31.006C.B05

SMC version (system): 1.25f4

Serial Number (system): CK******XYL

Hardware UUID: E655C9DA-02F9-5DE4-87E7-B22677******

As always, any help will be much appreciated.

Thanks.

[Edited by Moderator]

Earlier Mac models

Posted on Sep 17, 2025 07:36 AM

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Answer 1

Top-ranking reply

Grant Bennet-Alder

Level 10

138,791 points

Sep 17, 2025 08:50 AM in response to Otterysteve

<< BUT I really need to have a proper back up regime as old hard drives can die. >>

That older Mac's USB-2 ports are comparable in speed and will not cause any measurable slowing of even the fastest Rotating Magnetic drives. Adapters can be used to attach USB-3 and even USB-C drives. High quality adapters carry the USB-2 signals along, intact, in the interface.

That Mac COULD run up to 10.11 El Capitan, which would allow internet access directly if you wanted that. (But not high-end stuff like banking, which is increasing restricted to very recent browsers.)

--------

Major HUGE changes to maximum File sizes and maximum drive capacity were introduced in MacOS X 10.4, and have not needed to be touched since. You not mounting that drive is due to more complex reasons.

At MacOS X 10.13 High Sierra, Apple started to introduce Apple File System (APFS) as the default format for an SSD boot drive. This became the default format for almost all drives over time. When you look closely that the partition structure, it includes a container-disk, which encloses multiple active APFS Volumes.

at MacOS 10.13 Catalina, Time Machine's default format for NEW drives transitioned to APFS as well, but older MacOS Extended drives can still be used.

Older Macs do not understand container disks, so they just leave them alone. That is by design --

so that older MacOS will not try to "fix" an APFS drive, and mess it up in the process. The reason you could not mount a newer, already formatted drive because it is in APFS format, which MacOS X older than about 10.13 can't understand.

If you connected a drive in ExFAT format, or a drive in MacOS extended format, it would read that drive just fine. Your older Mac can read the drives you need it to read, it just can't share APFS drives directly with your newer Macs. Use Mac File Sharing (across your home network) instead. File Sharing launders out the details of how the file is recorded, and just provides Files directly, independent of how they are stored.

--------

As a reference point, 4 GB of RAM is not enough to run 10.11 El Capitan (just the Operating System) in an appropriately-responsive way. MacOS uses Virtual memory to allow you to run anything, but the performance hit is NOT negligible, especially with Rotating Magnetic boot drive.

Replacing a Rotating Magnetic boot drive with an SSD boot drive will also make everything MUCH more responsive.

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Answer 2

Sep 17, 2025 10:51 AM in response to Otterysteve

<< I CAN use new SanDisk Prof G-Drive ArmourATD hard drives with my old Mac Pro as Time Machine backups, so long as I use a USB adapter to connect the hard drives USB-C port to the Mac Pro please? And that they will work? >>

Sure. But the port on your Mac is USB-2 using a USB-A connector.

I think if you buy a new drive, it might come with an adapter. if not, You might even be able to use these, at about two for US$10

Be sure to get the sexes correct -- both converters are available. Try to choose a brand you have heard of before. If in doubt, use the genuine Apple adapter with a very short cord.

For the Time Machine drive, choose:

MacOS Extended (journaled)

<< (I haven't actually got a home network, just my Macbook Air which is connected to the internet). >>

If you have another computer in the house, you have a data highway available using the Switch functions of your Router. (Actually connecting to the internet is not necessary.)

An Ethernet cable or enabling Wi-Fi is all that is needed.

Then the options in

Sharing > File Sharing can be used.

-------

The 2008 Mac Pro you specified has 8 RAM slots. Install in pairs. As cheap as US$80 for 2*4GB, here:

https://eshop.macsales.com/shop/memory/owc/apple-mac-pro/2008

scroll down on that page for compatible SSD drives as well.

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Answer 3

Otterysteve Author

Level 1

13 points

Sep 17, 2025 10:23 AM in response to Grant Bennet-Alder

Hello Grant Bennet-Alder

Thank you very much for your reply.

To clarify, are you saying that I CAN use new SanDisk Prof G-Drive ArmourATD hard drives with my old Mac Pro as Time Machine backups, so long as I use a USB adapter to connect the hard drives USB-C port to the Mac Pro please? And that they will work?

And, being a new hard drive, it will need to be formatted by the Mac Pro for use as a Time Machine backup drive. Clearly APFS will not be an available option from what you say. I don't know what formatting options I will have, but maybe you do, and could you tell me which I should chose please?

My old Mac Pro isn't connected up to anything, not the internet or any home network (I haven't actually got a home network, just my Macbook Air which is connected to the internet).

I appreciate that I am a bit short of RAM, but it works with what I do. It's a stand alone system that I use for music making fro my own entertainment, and I have a lot of various software and hardware that I've accumulated over the years with it. I have no need really (as far as I am aware) to upgrade to El Capitan or anything else.

Thanks again for your help.

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Answer 4

Otterysteve Author

Level 1

13 points

Sep 18, 2025 04:54 AM in response to Grant Bennet-Alder

Once again, thank you very much Grant Bennet-Alder. Your replies are very helpful and much appreciated.

So I can use the external hard drives I specified, with an appropriate USB-A to USB-C adapter, formatting with MacOS Extended (journaled). The ones in your illustration would be the wrong kind as it needs to plug into the USB-A port on my Mac Pro 3.1. I have actually got an adapter, it came with some headphones, or I couldn't have got the message I did when I tried it with the external hard drive already formatted to APFS.

This is great news and thank you for your clear help.

As for the home network, very interesting. I'll have to try to explore that. I'm not sure how to go about using the Switch functions of my router. It's a Vodafone router and I have no idea where the Switch functions are. But file sharing directly from my Mac Pro to my Macbook Air would be very useful!

Thank you for the link to Macsales.com. I didn't know such stuff for my old Mac Pro would still be available. Unfortinately I live in the UK (that's not the unfortunate bit!) so I would need to find an alternative supplier here. I imagine carraige cost from the USA would be prohibitive. But I like the idea of backing up the old internal hard drives, then perhaps transferring this to new internal hard drives, to replace the old ones. Some more RAM couldn't do any harm either.

Thanks again Grant, your replies have been very helpful.

And while I remember, also big thanks to the Moderator who edited out some information I didn't mean to post. I had copied and pasted the specs for my Mac Pro without properly looking at what I was posting. Thank you Moderator, that was very helpful of you, much appreciated.

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Answer 5

Sep 18, 2025 10:43 AM in response to Otterysteve

<< The ones in your illustration would be the wrong kind as it needs to plug into the USB-A port on my Mac Pro 3.1. >>

if you mean the ones linked to the OWC memory page, those are intended to replace the BOOT Drive.

Since macOS is constantly 'snacking' on the boot drive -- loading a little of this program, saving some settings, writing or re-reading some pages to and from the Swap File, and so on -- having a faster Boot Drive makes for a faster system all-around.

<< Thank you for the link to OWC/Macsales...[...] ..Unfortunately I live in the UK >>

No matter where you are, OWC solutions are within your reach. Shop within the comfort of your home or visit one of our outstanding OWC Channel Partners around the world.

https://www.owc.com/partners/where-to-buy/?_gl=1*y0w6fq*_gcl_au*MzYwOTExNDYzLjE3NTU5MDgyMTg.

NB> be sure to click the (Load more) button to get additional reseller, there is one in Leeds, UK shown on second page and MegaMac and MR systems and Technology Express in London further down the list.

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Answer 6

Sep 18, 2025 10:52 AM in response to Otterysteve

<< As for the home network, very interesting. ...[...].... I'm not sure how to go about using the Switch functions of my router. >>

All you need to know is that that connection is already in place, and you can just use it. This article covers back to High Sierra, but it has not changed:

Set up file sharing on Mac - Apple Support

You can also share the screen of another [local] Mac on your network in a window on a Mac:

Share the screen of another Mac - Apple Support

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