Mac Pro Hands-On: Adding Additional SSD Storage Using a PCIe Slot

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When the Mac Pro became available for purchase a few weeks ago, we bought a base model and have since been demonstrating upgrades with third-party components for those interested in boosting their Mac Pro's capabilities without having to shell out for Apple's upgrades.

We covered upgrading the RAM in a Mac Pro in our last video, and today, we're demonstrating how to add additional SSD storage using one of the Mac Pro's PCIe slots.


The base model Mac Pro comes with 256GB of storage space, which isn't a lot in a professional machine. Luckily, it's easy to add additional storage if you purchase a compatible third-party SSD.

Completely replacing the SSD in a Mac Pro with a new one requires visiting an Apple Store or an Apple Authorized Service Provider because the built-in SSD is tied to the T2 chip that provides encryption and other security benefits, but the existing storage can simply be augmented if you have a free PCIe slot.

The Mac Pro has eight PCIe expansion slots, which allow for extra USB ports, graphics cards, audio cards, and more storage, so that's an easy way to get additional storage space. Note that what we've done here means the SSD we're installing is extra storage space and not a boot disk - it's been added in addition to the existing 256GB SSD the base Mac Pro ships with.

We added a 4TB NVMe SSD from OWC, which is priced at $950. That's a good deal cheaper than the 4TB SSD upgrade option from Apple, which is priced at $1,400. You don't need to use OWC, but third-party SSD options are much more affordable than what Apple is offering.

Installing a new SSD is as simple as popping the case off of the Mac Pro, unlocking one of the PCIe slots, unscrewing the brackets and inserting the card. That's all there is to it. Once the case is back in place and the Mac Pro is booted up after installing a new SSD, the drive will show up on the desktop.

The OWC Accelsior 4M2 SSD we installed claimed to offer transfer speeds up to 6000MB/s. In our testing, we didn't quite see those speeds, but we did see write speeds at 4786MB/s and read speeds of 5360MB/s, which is much faster than the built-in SSD, which hit write/read speeds of 1312 and 2232MB/s, respectively.

When it comes to real life usage, that meant we were able to transfer 50GB of RAW video files to the OWC SSD in just about 20 seconds, a process that took 40 seconds with Apple's SSD. So it's entirely possible to get a faster SSD than what Apple's offering at a lower price. An OWC model is not required, of course, and for those with a Mac Pro interested in upgrading, it's worth doing some research to find the best price to save money.

We'll have more Mac Pro videos coming in the future, including a look at the Promise Pegasus R4i MPX RAID storage module designed for the Mac Pro.

Article Link: Mac Pro Hands-On: Adding Additional SSD Storage Using a PCIe Slot
 

bsbeamer

macrumors 68040
Sep 19, 2012
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Those OWC cards are x8 PCIe cards and not exactly getting rave reviews in the Mac Pro forums. Suggest people look at these x16 cards for better performance:

Sonnet M.2 4x4, but pay attention to the NVMe blade restrictions

HighPoint 7101-A, but make sure you get the latest model so you can enable silent mode
 

MauiPa

macrumors 6502a
Apr 18, 2018
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"The OWC Accelsior 4M2 SSD we installed claimed to offer transfer speeds up to 6000MB/s." footnote:
Work Faster: over 6,000MB/s real world speed in RAID 01. Doesn't this explain the discrepancy in your test versus the claim? It did not sound like you set your drive up as RAID 0, hence you should not expect to see RAID 0 speeds.

I do not believe the boot drive can be RAID 0, but you may still be able to use this drive at a slower speed as boot drive, but why?

4TB drives are faster than 256 GB drives, I probably would have mentioned that in the article, the 4TB Apple option is probably much faster as well.

50gB/20 seconds = 2500 MB/sec write speed
 
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aajeevlin

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Mar 25, 2010
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Many years ago when I got my first job I told myself eventually I’ll get a Mac Pro (that was when the starting at $3000) I think. Fast forward to 2020, starting is at $6000, basically priced out most of the Mac lover. So at this point as much as I love the new line I’m looking at continue to use my 2009 bought used Mac Pro or an iMac if I want a desktop. Sigh, maybe a few more years.....
 

Mdracer

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Jul 1, 2016
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...and the heavens started opening.

I would love to see it proven to choose this SSD as the OS start up drive.
 

Logic368

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Oct 17, 2011
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Many years ago when I got my first job I told myself eventually I’ll get a Mac Pro (that was when the starting at $3000) I think. Fast forward to 2020, starting is at $6000, basically priced out most of the Mac lover. So at this point as much as I love the new line I’m looking at continue to use my 2009 bought used Mac Pro or an iMac if I want a desktop. Sigh, maybe a few more years.....
You know, I was like you a while back. Always wanted the fastest Mac ever. However, now, my setup is just a MacBook Pro connected to an external display in clamshell mode. Much better and versatile than locking yourself into something like the iMac.
 

Michael Scrip

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Mar 4, 2011
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Those are sequential speeds which don't matter... post the real world random speeds, then we'll talk.

Note: Sequential speeds matter only in files which are huge (GB in size). Like this test. Even video files are many times built from several clips from other files. So in a sense, it's a pointless test as well.
Exactly.

I always wonder if a computer will actually hit these crazy MULTI-GIGABYTE speeds in daily tasks.

Sure... it's fun to run a speedtest and get such high numbers. But like you say... it's just a sequential benchmark.

Probably the only time you might experience these speeds is if you're copying files from one of these insanely fast drives to another insanely fast drive.

Don't get me wrong... that's pretty cool. But how often are you copying a bunch of files from one SSD to a different SSD?

If you're a video producer... the first copying task is from your memory cards. And those are VERY slow by comparison... measured in only hundreds of megabytes per second. That's your bottleneck.

But once all the files are on the computer... will this drive actually be faster while you're editing?

Will you notice a difference between this 6,000MB/s RAID versus a single MVNe drive that is only 2,000MB/s?

I love speed. But there's gotta be a point of diminishing returns.
 
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fmcshan

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Apr 8, 2019
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The modularity of the Mac Pro is why I really like it. I wish the SSD was accessible and easily upgradable in Apple's iMac/MacBook lines.
 
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tallscot

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Mar 30, 2002
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The modularity of the Mac Pro is why I really like it. I wish the SSD was accessible and easily upgradable in Apple's iMac/MacBook lines.
Having to use a PCI card to add another SSD, and not being able to just swap out the boot SSD, is very disappointing for a “modular” computer. My son’s gaming PC we built for $900 has interfaces on the ribbon cable and mount screws built into the side of the $80 case - just pop it in and plug in the cable.

I guess Apple will never ever give us the same flexibility as a Windows PC.
 

foobarbaz

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Nov 29, 2007
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In our testing, we didn't quite see those speeds, but we did see write speeds at 4786MB/s and read speeds of 5360MB/s, which is much faster than the built-in SSD, which hit write/read speeds of 1312 and 2232MB/s, respectively.
Recently, the smallest SSDs that Apple ships are often significantly slower than their big SSDs.
So I wonder if it's still faster than Apple's 4TB option.
 

ThomasJL

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Oct 16, 2008
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On the new Mac Pro, is TRIM support enabled by default for third-party SSDs? If not, can a user enable TRIM support without having to use the command line?
 
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Yoms

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Jun 1, 2016
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Can someone explain why - according to the figures provided in the article - the write speed of Apple's SSD within the Mac Pro (1312MB/s) is slower than the SSD within the MacBook Pro (2519MB/s for the 2018 model as reported here)?
 

RONS67

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Aug 15, 2016
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Highpoint Technologies has a 4x4 nvme m.2 RAID card that benchmarks twice as fast as this. See also barefeats dot com for an Amfeltec 6-slot card that is even faster.
 

killermike2178

macrumors member
Aug 23, 2012
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HighPoint 7101-A, but make sure you get the latest model so you can enable silent mode
I second the HighPoint 7101-A. Allegedly, you can get two of those and get up to 16TB of NVMe drives that can all be combined as 1 RAID0 array through their Cross-Sync drivers that allegedly are supported by macOS and can get R/W speeds of up to 28,000 MBs...

 
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CWallace

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Can someone explain why - according to the figures provided in the article - the write speed of Apple's SSD within the Mac Pro (1312MB/s) is slower than the SSD within the MacBook Pro (2519MB/s for the 2018 model as reported here)?
Larger-capacity SSDs have better performance (more cells to work with). So the 512GB SSD in the MBP has better performance than the 256GB SSD in the MP.
 
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Marx55

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Jan 1, 2005
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Is there a way to configure Blackmagic Disk Speed Test to show the maximum speed, instead of keeping resetting itself for ever, which is utterly FRUSTRATING?!
 

MauiPa

macrumors 6502a
Apr 18, 2018
713
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Having to use a PCI card to add another SSD, and not being able to just swap out the boot SSD, is very disappointing for a “modular” computer. My son’s gaming PC we built for $900 has interfaces on the ribbon cable and mount screws built into the side of the $80 case - just pop it in and plug in the cable.

I guess Apple will never ever give us the same flexibility as a Windows PC.
Wow, just wow!
 

Wedlock

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Jul 27, 2010
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St Willebrord , The Netherlands
I would think you could use such a device as a bootable drive even though there is a T2 chip in there.
I have a 2018 Mac mini which has the T2 and I created an bootable drive for the mini with a Samsung X5 on Thunderbolt 3 and it worked perfectly.
Yes this is external but that should not matter......

Also Apple states on their site that there is a maximum read/write speed for Mac Pro of up to 3,4 GBs so this would still be faster.
 
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fermat-au

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Dec 7, 2009
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You know, I was like you a while back. Always wanted the fastest Mac ever. However, now, my setup is just a MacBook Pro connected to an external display in clamshell mode. Much better and versatile than locking yourself into something like the iMac.
I completely agree with you about the iMac.
I have never liked the iMac as a concept, it is the worst of a laptop — un-upgradable and inflexible — and the worst of a desktop — not portable. A laptop with a large external display is a much better solution overall, you have a portable laptop and when the laptop becomes dated, you still have a display that can be used with another system.
 
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