Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

rondocap

macrumors 6502a
Original poster
Jun 18, 2011
543
346
Also being a Mac and PC enthusiast, I am used to having a lot of information and discussion on hardware, which generally is readily available in that PC world. (I have a YouTube channel on pc tech, but talk about Mac stuff occasionally too - "Classical Technology" on there)

The 2019 Mac Pro is a fascinating machine both for its capabilities, as well as the limitations imposed by Apple.
w as
No other component is more varied than the GPU - as it is the key to a lot of workflows, especially for video editing.

I wanted to have a thread here to summarize different experiences and info related to GPUs, both what I have found out so far as well as everyone else giving their input - because a lot of these questions are spread out on the internet here and there but not very conclusive when it comes to the Mac Pro and GPUs, so many questions remain, being a niche system, it is understood why that is so.

So I'll just mention somethings I have had questions about and found answers too, and feel free to add yours below as well!

A lot of times you'd think throwing powerful hardware/GPU at a problem you are having will solve it, but it is not always the case with video, such as what the M1 Macs are capable of doing in the real world vs their specs on paper, like 422 10 bit, etc.

Note - My experience is geared towards using these GPUs for video editing, primarily FCPX and Davinci Resolve, but no Adobe.


1. What is the best performance for the dollar GPU setup to get right now?
A.) I have found that Dual MPX W5700x, coming in at around $2000, seems to be the best price to performance. It performs very close to a single, more expensive Pro Vega ii, and has some benefits in the new architecture such as faster encoding 10 bit, etc.

2. What about the ultimate GPU performance?
A.) Obviously the Vega ii duo is very powerful - but I would hesitate to get these right now for video editing because the new AMD 6000 GPUs are possibly on the horizon as MPX modules, and the beta performance thus far in some cases of the 6800xt, 6900xt, are really next generation and seem to have significant improvements that may translate better for FCPX/Resolve for cheaper vs the duo which is older tech at this point. (Albeit still very capable)

3.) What is the status of AMD 6000 GPUs?
A.) Big Sur Beta 11.4 finally gave us the ability to have the 6800, 6800 XT, and 6900 XT standalone GPUs installed. No 6700 XT as of now, though. I would expect the official MPX modules to follow sometime this year too, makes sense and the performance is definitely promising and a big upgrade judging from the beta so far.

4.) How are the AMD 6000 GPUs working at the moment under the beta?
A.) First, performance has been stable on the Mac Pro and on an eGPU connected iMac Pro in terms of no crashes, etc. Davinci Resolve for me has not worked well, I think the app needs an update as I am getting very slow performance at the moment in that app. FCPX is taking much more advantage of the GPUs though, but of course it is beta so still needs optimization. Bruce X score was really fast with a 6800XT, under 6 seconds which was close to the time of dual W5700x and beat the single Pro Vega ii as well. Metal scores are very high, 6800xt 145,000+.

5.) Dual W5700x plus the 6800 XT at the same time
A.) I tried this, but performance in FCPX didn't really seem to take advantage of this, and In Resolve, made it worse. It's likely just beta issues and eventually should be better optimized - but all gpus are at least recognized.

6.) Fillng up your PCIE slots, what to know:
A.) So using dual MPX Module certainly takes up a ton of space in the Mac Pro, so just be aware of that - I am still able to fit a smaller GPU like a 6800 or Vega 64 reference, and something like a Sonnet PCIE NVME card, with the stock apple I/O card. Keep in mind the 6800xt reference is thicker than the 6800 or Vega 64, and it takes up an additional slot, so you're limited on adding other PCIE cards.
Ideally I think dual MPX modules are fine, still gives you room for PCIE NVME/SSDS, etc. Three GPUs not really much benefit yet for FCPX or Resolve at the moment.

I stick with the reference AMD GPUs, keep in mind some third party GPUs are massive and may not fully fit inside the Mac Pro, so do your research before going that route.

7.) The Apple Afterburner card
A.) Yes, the idea is exciting - but the real world implementation seems to be very limited - basically Pro Res Raw and Pro res workflows, and even then, there are more limitations, such as not really helping with background rendering, decoding, etc. I think unless you are doing straight pro res raw, 8k, multiple streams, which the Mac Pro already handles well in most cases, that money is better spent on the GPUs.
But it doesn't keep me from wanting to try it though, and move to a more Pro Res environment.

8.) How does the Mac Pro do with Canon R5 10 422 codecs?
A.) Not ideal, even the 6000 AMD GPUs or a PC Nvidia 3090 has trouble with the 422 10 bit specifically. Basically you need an M1 Mac, those have the hardware necessary to laughably easily work with this footage. It's not a raw power issue, but just a codec specific optimization that I don't believe will ever be possible on current hardware, so the M1 Macs/ iPad Pro are the best bet.

9.) Can you mine crypto on a Mac Pro? (I know, bare with me here, but it is a question people ask!)
A.) In bootcamp it is easier to do so, with something like nice hash or mining to a pool directly. Keep in mind it is not really easy to tune the GPUs, like if you have MPX W5700x or a Vega ii, they aren't as "tunable" as a PC counterpart, and their hash rate to power draw ratio isn't very good. At this very moment prices are so high that they actually do work and make sense, but as soon as it drops again, the power draw makes it not the best or efficient option. But it can be done for those curious, even if it is not the point of this machine entirely.

10.) Will an MPX module, like a w5700x, and a regular GPU like a Vega 64 work in windows?
A.) With special bootcamp drivers they can work together in windows, but keep in mind if you are using a TB3 display, be ready with an HDMI monitor solution because sometimes the driver can switch over to the regular Radeon ones and not the Apple ones depending on which you download, and you may lose the output from TB3. But with the special bootcamp drivers both seem to work together in windows.

11.) CPU for video editing, how many cores are enough? (GPUs are still king now of course for most workflows)
A.) When ordering from Apple, people generally recommend the 12 or 16 core as the sweet spot for video editing. I upgraded my base 8 core with the W3265M 24 core xeon - at a significantly lower price than if I got it from Apple, so IMO on the upgrade side if you're doing it yourself the 24 core is actually the best value. I got mine for $1600, OEM and not engineering sample. 12 or 16 core are only a few hundred cheaper on the used market, and the 28 core is around $800-1000 more, so the 24 core seems like a good deal here. Obviously if ordering new, the 12 or 16 are a better value at that point directly from Apple as their 24 core price is much more.

Is it worth it having 24 cores? Video editing is heavily GPU based, but in many cases it will light up those 24 cores, like when working with Pro Res Raw, doing certain codecs, effects, etc - so IMO the machine can definitely make use of it and it is certainly not a waste.

Likewise with ram I found the sweet spot to be 96GB for my workflow, it rarely goes above 64gb but does do so on occasion. Definitely passes 32GB easily, though.

12.) At what point does the Mac Pro stop making sense vs a PC?
A.) This is the tough question that always comes up. For comparison, I also have a 3960x 24 core Threadripper with dual Nvidia 3090 GPUs, which in terms of raw power is significantly more powerful than anything the Mac Pro would be capable of.

But then we get into the app preference - I like Mac OS and the way things flow, and I enjoy working with FCPX. Having said that, Windows has also improved in recent years, and If I were to use just Davinci Resolve which is getting more and more popular, there is no doubt that the raw power and immediate access to the latest PC hardware upgrades without having to wait for Apple are also pretty significant to consider.

I mean...on the Apple side we get excited about a W5700x or even the Vega ii, and some even put up with a 580x. Those GPUs are in some cases generations behind the PC side. For now the situation is OK, they are powerful enough in Mac OS for most workflows, and with the AMD 6000 now being supported, we should be ok for a few years in terms of power.

But the moment Apple starts to let the Mac Pro hardware go too long without upgrades, it's going to turn into a less desirable machine like the trash can - best case it will be like the cMac Pro cheese grater and have an enthusiast audience left, but anyone needing raw power will switch to whatever Apple Silicon or the PC side.

The heart of the Mac Pro is the GPU (Unless you're in audio of course, I am talking mainly video editing here) so the good news here is that it is easy to upgrade and with PCIE slots, we have a lot of options as long as Apple provides the proper drivers for GPUs in the future. Are there faster CPUs out there? Sure, but even the current Xeons are capable for video editing and not out classed completely yet - the real bread and butter is on the GPU side as that's what is important now.


Let me know other things you've come up with as well!
 
Last edited:
  • Like
Reactions: blackquartz
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.