Monday, June 5, 2023

Mac Pro 2023

Apple (MacRumors, Hacker News):

Mac Pro, now featuring M2 Ultra, combines the unprecedented performance of Apple’s most powerful chip with the versatility of PCIe expansion. Mac Pro is up to 3x faster than the previous-generation Intel-based model. Featuring up to 192GB of unified memory, Mac Studio with M2 Ultra and Mac Pro have far more memory than the most advanced workstation graphics cards, taking on demanding workloads other systems can’t even process. The new Mac Pro completes the Mac transition to Apple silicon and, together with the rest of Apple’s pro systems, gives users the most powerful and capable lineup of pro products Apple has ever offered.


The wide array of connectivity in Mac Pro gets even better with eight built-in Thunderbolt 4 ports — six on the back and two on the top — which is twice as many as before. It supports up to six Pro Display XDRs, along with Wi-Fi 6E and Bluetooth 5.3, which come to the new Mac Pro for fast wireless connectivity. Additionally, Mac Pro includes three USB-A ports, two higher-bandwidth HDMI ports that support up to 8K resolution and up to 240Hz frame rates, two 10Gb Ethernet ports, and a headphone jack that enables the use of high-impedance headphones.


Available in both tower and rack-mounted enclosures, Mac Pro (Tower Enclosure) starts at $6,999 (U.S.) and $6,599 (U.S.) for education. Mac Pro (Rack Enclosure) starts at $7,499 (U.S.) and $6,999 (U.S.) for education.

There’s no quad chip, and the RAM and GPU are no longer upgradeable.

Juli Clover:

Following the introduction of the Apple silicon Mac Pro, Apple today added SSD upgrade kits to its online store. The kits offer 2TB, 4TB, and 8TB of storage space for $1,000, $1,600, and $2,800, respectively.


Update (2023-06-06): Stephen Hackett:

However, it also comes with all the downsides of being an SoC. Gone is the 1.5 TB RAM limit of the 2019 Mac Pro, but more importantly, gone is the ability to add RAM after purchase. The same thing goes for upgrading the GPU.

The truth in 2023 is that Mac Pro you buy today will be the same core machine in five years, and that’s just not something we’re used to seeing when it comes to this machine.


Several of us who cover Apple have heard that there are those inside the company that did not want this machine to see the light of day, believing the Mac Studio to be enough to hold down the high-end of the Mac line. Seeing the machine that Apple announced this week, I think they may eventually get their way.

Update (2023-06-07): Nick Heer:

And, if you do choose to compare this Mac Pro to the Intel model it replaces, there are some changes which are difficult to swallow. It is $1,000 more expensive than the one it replaces. The outgoing model was endlessly upgradeable with dedicated video encoding hardware, graphics processors, and up to 1.5 terabytes of memory. The M2 Mac Pro appears to support none of those things. Apple has tried to preempt criticism by claiming this version effectively has the power of seven Afterburner video encoding cards built in, but there are no known differences between the M2 Ultra in the Pro and the one in the Studio. Even its PCIe slots are being marketed for comparatively less demanding workflows:

Update (2023-06-09): Colin Cornaby:

The new Mac Pro is hilariously disappointing.

Mike Piatek-Jimenez:

I’m a little surprised the Apple silicon Mac Pro didn’t go directly to PCIe 5 support. That’s been standard on desktop and server PC hardware for months now.

Francisco Tolmasky:

The best part about the Mac Pro is that it looks like a “platform” that can be updated yearly. They can just keep putting the new M-whatever chip in it (& hopefully eventually figure out how to quadruple it vs. just having the Ultra). Ideally they can bump it up to PCIe 5 and Thunderbolt 5 “easily” too. In other words, the fact that this is so similar to the Mac Studio means it hopefully won’t suffer the same fate as the previous “one-hit wonder” Mac Pros. Looking forward to M3 Mac Pro…

Hartley Charlton:

The main reason to buy the Mac Pro is to be able to use its seven PCIe expansion slots add the likes of digital signal processing (DSP) cards, serial digital interface (SDI) I/O cards, additional networking, and built-in storage. This also allows a user to change some of their Mac Pro’s hardware over time, and Apple is offering additional do-it-yourself SSD upgrade kits and wheels for the device.

If you require multiple Ethernet ports, more than six Thunderbolt ports, or more than two USB-A ports to connect a large number of peripherals, only the Mac Pro can facilitate this. Otherwise, since the Mac Studio can be configured with the same M2 Ultra chip as the Mac Pro, there is no reason to buy the more expensive desktop machine, and most users will be better off buying the Mac Studio and saving $3,000.

See also: Accidental Tech Podcast.

Update (2023-06-13): Joe Rossignol (Hacker News):

Apple’s hardware engineering chief John Ternus briefly touched on the matter in an interview with Daring Fireball’s John Gruber last week, explaining that expandable GPU support for Apple silicon is not something that the company has pursued.

Desire Athow:

Apple specifically calls out rendering performance in Octane, Redshift and Blender in the keynote and, according to Kelly Shipman, the company’s resident hardware expert, the lack of GPU support is very limiting for rendering.

Ryan Jones:

Mac Pro as-is is certainly dead. The empty tower is SO obviously just cuz Ternus said so.

Hector Martin:

Yeah okay so they are totally cheating.

They have two big PCIe switches and are hanging everything off of them.


So basically 5 of the slots including both x16 ones are bottlenecked into a single x16 gen4 channel. Boo.

Via Colin Cornaby:

Is Apple just intentionally trying to kill the Mac Pro?

This should be a $3000 system. PCIe bandwidth is one of the big reasons to buy a workstation at workstation prices. Along with all the other changes Apple made - there is no reason anyone should buy this thing.

Colin Cornaby:

The PC I just build for a fraction of the cost of the Mac Pro has…

  • 20 PCIe Gen5 lanes compared to the 16 PCIe Gen 4 lanes on the Mac Pro (and 20 lanes is already pretty minimal.)
  • A 13900k which beats M2 Ultra in both single threaded and multithreaded workflows.
  • A GeForce 4090k which is solidly faster than M2 Ultra.
  • Expandability

All this for a fraction of the cost of the Mac Pro.

Brendan Shanks:

I guess the new one doesn’t even have ECC RAM?

Honestly it feels more coherent to think of this as the “Mac Studio Pro”, and there just isn’t an actual Mac Pro anymore. A casualty of the ASi transition.

Update (2023-06-15): Colin Cornaby:

When the 2019 Mac Pro was released - Apple implied that the Afterburner card was reprogrammable and could be used for other things. I wonder what happened with that. That seems like something that could have still been useful in the new Mac Pro - even though M2 has ProRes encoding pretty well covered.

Ben Lovejoy:

So what can you plug into them? Apple has listed the main options[…]

Some have questioned the limited power availability if you want to make full use of the card slots. That’s because each slot is limited to 75W of power. However, Apple says there’s a solution to this.

Update (2023-06-16): John Siracusa:

I’ve had over a week to digest the new Mac Pro. I try to put it in perspective on the latest episode of @atpfm.

Update (2023-06-27): Monica Chin:

I wanted to know whether Apple’s purported target demographic — people who spend their days animating, making visual effects, and doing various other tasks generally associated with big, powerful computers — were actually interested in purchasing this machine. So I asked a bunch of them, and the answer, basically across the board, was no. Not because the Mac Pro is bad but because Apple’s other computers, namely its laptops, have just gotten too good.

Update (2023-07-10): See also: Accidental Tech Podcast.

16 Comments RSS · Twitter · Mastodon

Apple did the math and after reviewing vast amounts of user data, trends and opinions decided do not need to support add-on GPUs for Pro workflows.

2019 Pro maximum configuration has 1.5 TB of DDR4 ECC RAM and x2 64 GB of DDR6 VRAM (Two Radeon Pro W6800X Duo). Communicating via x16 PCIe 3. Wondering who needed it.

Old Unix Geek

@Wu Ming: or they simply decided they didn't want to support 3rd party drivers.

Have to admit I’m a little disappointed they didn’t find a way to make an M2 Extreme or something. I don’t need that power — heck, I don’t even need an Ultra — but it would have been great to see a stake in the ground. Pour one out for all 2 people who needed 1.5TB of RAM for… something.

@Old Unix Geek perhaps. But then I do not understand why. Drivers are slowly evicted to user space already. If security is the main concern. I think performance has more to do with it since AMD may not be available to invest enough to support such an uncommon configuration. But have no numbers to sustain my speculation.

Another point of interest: did they mention ECC for the new Pro?

From what I'm seeing on the website, if you want a base Mac Pro, you can basically get the same specs aside from an additional HDMI port, an additional ethernet port, and the expansion slots for $3000 less by just getting an M2 Ultra Mac Studio. That's pretty crazy!

Old Unix Geek

@Wu Ming: it sounds like ECC codes are kept in main RAM for LPDDR5. That means one would expect such systems to report a non power of 2 RAM size.

This is where the terminology becomes infinitely confusing, because the idiots at the IEC redefined what a gigabyte is. It used to mean 2^30 (two to the power 30). Now it is 10^9, and 2^30 has been officially renamed a "Gibibyte", but few people use that term.

Apple tells us it ships a 64Gb Mac Pro. If Gb means "gibibyte", then the answer is no ECC.

Why? because if 8 bytes are reserved for ECC per 128 bytes of data, 64 Gibibytes of RAM would be reported as 60 gibibytes:

128 * (64 * 1024 * 1024 * 1024 / (128+8))) / (1024*1024*1024) = 60.23...

The reason I don't think they use the new power of 10 meaning of Gigabyte for RAM, is that they specifically say they do for the flash drive storage, and in general DRAM has stayed with the old meaning of Gb, whereas storage has adopted the new meaning (since they can sell more for less -- the difference between 1 tebibyte and 1 terabyte is 92 gibibytes which isn't nothing).

Apple may however have a parity bit computed on the fly between the in-package LPDDR5 and the Apple chip to ensure data got there correctly.

@OUG Yes, Apple likes to use binary for counting memory.

Old Unix Geek

@Michael Tsai: thanks!

>Have to admit I’m a little disappointed they didn’t find a way to make an M2 Extreme or something.

I'm guessing they looked at 2019 Mac Pro sales and 2022 Mac Studio sales and realized: 1) the M1 Ultra variant sells, but something above that likely won't. 2) Some customers have very specific PCIe demands; let's make a machine that offers them. 3) Third-party GPUs, ECC, extensible RAM, or RAM in general above 192 GiB? Not worth it.

>From what I'm seeing on the website, if you want a base Mac Pro, you can basically get the same specs aside from an additional HDMI port, an additional ethernet port, and the expansion slots for $3000 less by just getting an M2 Ultra Mac Studio. That's pretty crazy!

Yes, it's a wild difference. The Mac Pro offers very little (one thing you don't mention is upgradeable internal SSD, if I understand this correctly) that the Studio doesn't.

I _guess_ better thermal headroom and therefore virtually zero noise is another thing in its favor. But is any of that $3000 in its favor? For very, very few people, surely.

> the idiots at the IEC redefined what a gigabyte is

The idiots at the IEC simply looked at what the giga prefix means in LITERALLY ANY OTHER CONTEXT, not what some arithmetically-challenged Silicon Valley dude who suffered from imperial units thought it should mean.

> Yes, Apple likes to use binary for counting memory.

Which is a real bummer because "GB" in macOS now means different things for RAM and hard disk. But I get it. Were they gonna say "your computer has 16 GiB RAM"? That's correct, but weird, so they chose not to.

(The other choice would've been to correct the amount, not change the unit. So display 32 GiB RAM as 34.3 GB RAM. Also correct, but weird.)

Old Unix Geek

It seems, Sören, that you must be an aspiring idiot who likes redefining terms that have had accepted meanings since before you were born. A Kilobyte has meant 1024 bytes since 1969 at least.

The rule was pretty simple "kilo" is 1000 in base 10 (since 1795), and 2^10 in base 2 (since 1969). Computers are binary, i.e. work in base 2. Somehow, all of us dinosaur engineers could wrap our minds around such a difficult concept without much effort.

But I guess redefining words to create confusion is all the rage among those born after 1980, including words whose meanings most likely date back to the first invented languages. Objective truth? Hah, only when I want it!

Old Unix Geek

Oh, and 1024 has nothing to do with imperial units.

@Old Unix Geek thanks. What a rabbit hole. Originally I thought Apple was using the heavy copper heat spreader as cosmic radiation shield. But could not find confirmation of effectiveness against alpha radiation. And now Pro doesn’t have it. You are probably right it should be integrated within Ultra.

Another curiosity of mine is the potential implementation of RDMA and TB4 aggregation to form a cluster of either Studios or Pros. Pro caters I/O heavy workflows but memory and raw computing power are still limited to one system only. Any thoughts about it?

Old Unix Geek

@Wu Ming:

re RDMA/TB4 -- interesting question, but I can't help you with it. Sorry!

@Old Unix Geek it’s all right. Perhaps is how rendering farms work already. Aggregation of TB4 should just add bandwidth.

Was doubtful about your earlier: “ECC codes are kept in main RAM for LPDDR5”. Why Pro should use low power DDR? As it happens I just discovered Studio does. So is likely Pro does as well. Strange but true.

Also found your calculations a bit convoluted. To me was straightforward 64 - ( 8 / 128 ) * 64. Same result obviously and I am sure you thought about it as soon as posted. Sometimes explaining something in writing interfere with the optimization process. I had the benefit of reading your effort to think at the next step haha.

Old Unix Geek

@Wu Ming: I converted everything to the same unit (bytes) for the calculation since the equation deals with bytes (128 and (128+8)) and gibibytes (64 Gb), and then converting back to gibibytes. Obviously the equation can be simplified, but to me, not skipping steps is clearer. After all, I could have just answered "not likely" to your question =:-)

>So basically 5 of the slots including both x16 ones are bottlenecked into a single x16 gen4 channel.

That's quite disappointing.

It feels like _that_ was the main argument to have this product at all: internal, high-bandwidth PCIe slots. If they're not high-bandwidth, that leaves… two advantages over an external Thunderbolt case? Lower latency, and having it all in one and the same case.

Doesn't seem like a great deal at $3,000.

Still unclear how much of this is "this is roughly how much we're willing to invest in an architecture used by a single product" vs. "our original plans had to be postponed, this is the bets we can do as a a stopgap". Will the M3/M4/M5 Mac Pro, assuming any of those exist, be similar?

Leave a Comment