AndreeOnline

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I was thinking about the following setup, even if I assume the chance of success is low....

The coming iMac Pro as an on-the-desk computer paired with my current 5.1 Mac Pro on the floor.

The Mac Pro would be hooked up to the iMac Pro via DisplayPort to USB-C cable. It would be running with me logged in and that would in theory allow me to just CMD-F2 between the computers to go in and out of 'target display mode'.

I would strip the Mac Pro down and use it for dual 1080 Ti:s and storage. I would for instance setup a GPU assisted render on the Mac Pro and then CMD-F2 switch back to the iMac Pro as my main usage machine.

These two computers will never be officially supported to work together, but what would the actual limitation be here?

iMac and 'Target Display Mode' just wants a user to be logged in on MacOS on the other side of the cable. Would it really matter if it was an old Mac Pro if I'm using High Sierra on both? Would it actually matter that the 1080 Ti would probably have Display Port and not Thunderbolt or USB-C, if I use an adapter?
 

h9826790

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I think the Target Display Mode was gone when the 5k iMac released. Even on the 2011-2014 iMac, a Thunderbolt OUTPUT is required to make it work, which never happen on any cMP.
 
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AndreeOnline

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The thing is, the solution I'm looking for is pretty basic:

The OS needs to understand CMD-F2, and then essentially ask its host computer: do I sense another video in signal on any port? If yes: handover to that computer.

The other computer needs to understand the handover command, and later on, in turn, be able to handover itself via CMD-F2.

But yes, in the case of the cMP, there would need to be a USB cable involved too somehow for the data communication.

I've never really used TD mode and I didn't read up on it enough if it really is no longer supported. It just makes sense to me for an iMac to always be able to serve the role as "just the display" if need be. I see no reason for Apple to remove that function.

Oh, well... it will be interesting to see where a fully loaded iMac Pro lands price wise. Won't be cheap.
 

h9826790

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The thing is, the solution I'm looking for is pretty basic:

The OS needs to understand CMD-F2, and then essentially ask its host computer: do I sense another video in signal on any port? If yes: handover to that computer.

The other computer needs to understand the handover command, and later on, in turn, be able to handover itself via CMD-F2.

But yes, in the case of the cMP, there would need to be a USB cable involved too somehow for the data communication.

I've never really used TD mode and I didn't read up on it enough if it really is no longer supported. It just makes sense to me for an iMac to always be able to serve the role as "just the display" if need be. I see no reason for Apple to remove that function.

Oh, well... it will be interesting to see where a fully loaded iMac Pro lands price wise. Won't be cheap.

Target Display Mode only turn the iMac into a display, will not transfer the Keyboard / mouse control to another Mac. That's why on the pre 2011 Mac, Target Display Mode can work with any display port output. The post 2011 iMac didn't offer any extra function, Apple just make people cannot use the iMac as display for any non TB supported Mac (same as the Thunderbolt Display).
 

PowerMac G4 MDD

macrumors 68000
Why not just get an eGPU (assuming the case can take two cards) + a nice RAID box? I'm assuming that the iMac Pro would serve just fine as the rendering machine, especially with external graphics.

You could likely sell the Mac Pro, with stock configuration, and use that money for the eGPU chassis and external disks.
 

AndreeOnline

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Why not just get an eGPU (assuming the case can take two cards) + a nice RAID box?

Mostly because I already have my Mac Pro and some render jobs can run for a few days. It always find it a bit annoying to have one main workstation knowing that when I push 'render', I will be tying up much of the resources of that computer.

When I had a 1080 Ti in my 5.1 and rendered a Maxwell project via GPU, it was very quiet—minded it's own business. Went for days straight with no issues. Same goes for CPU renders, even if it produces a bit more noise (more like a low key humming). The new iMac Pros can be specced to have render grade grunt—at least on the CPU side—but I'm still not convinced it will be happy running for days at a time with 100% CPU utilisation.

I've been very happy with my Mac Pro, so I'm leaning towards waiting for the new one. But I think it will be a very hefty investment to get a new Mac Pro with 18+ cores and dual GPU.

That said, I think the new iMac Pro with a dual eGPU box and some storage would be a pretty able computer.
 
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William Payne

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Jan 10, 2017
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Speaking of cores and utilisation. Puget systems did a test with Premiere Pro seeing how the new i9's perform. They found that the 14 core i9 is actually faster then the 18 core i9 and that Threadripper is not a good choice for Premiere Pro.

Sorry slightly off topic but just reminded me.
 

AndreeOnline

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I roughly think about performance in 3 tiers:

  1. GAMING: highest possible CPU freq. To obtain this, you normally have to get fewer cores. Games.
  2. CREATIVE: this is my middle of the road tier that mainly works like the Case 1, but sees increased performance in a number of scenarios where softare performance scales with multithreading. Often it's just one or two tasks in the software that is fully multithreaded while the rest works more like a game would. Photography, Graphic Design, Video Editing, some Compositing.
  3. PRODUCTION: Just like the other tiers, a lot of stuff will still rely on fast single thread performance, but here we also have enough tasks that are fully multithreaded, so that the increased cost and some lost single thread performance is outweighed by gains elsewhere—lose 5 seconds here, gain 4 hours there. Simulations, Rendering, some Compositing.

This is roughly how I think about it in my head, but in reality everything blends together. It's up to the user to acquire information and apply knowledge.

It would be nice if people on forums start talking in less 'black or white' terms and see things for how nuanced it really is.

And yes, it kind of sucks to be stuck between case 1 and 3, wanting to get the most out of both scenarios. I would REALLY like to see Apple innovate in a real way here. Isn't it the iPhone X that uses a custom configuration of dual high speed CPUs and four slower ones that kick in for multithread? I'd love to see a Mac Pro with 4 super fast cores and 12 slower ones that sit back and kick in where needed. OK, then... 10 super fast and 64 slower ones.... =)
 

William Payne

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Jan 10, 2017
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Wanganui, New Zealand.
If a persons work is using specific software every day. I think it's a good habit to learn what the software will actually take advantage of.

I think single and multi threading gets forgotten about amongst the drewling and salivating people do over high core count CPU's.
 

AndreeOnline

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If a persons work is using specific software every day. I think it's a good habit to learn what the software will actually take advantage of.

For sure.

I think single and multi threading gets forgotten about amongst the drewling and salivating people do over high core count CPU's.

The thing is, for me at least, I'd like to see real benchmarking. Theory is good for entertainment prior to launch, but after that it's all benchmarking using the hardware and software combination that one plans to use.

Game benchmarks don't belong in a production environment and vice versa.

A surprising result doesn't mean its wrong. Sometimes that's how the dominos fall.
 

William Payne

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Jan 10, 2017
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Wanganui, New Zealand.
For sure.



The thing is, for me at least, I'd like to see real benchmarking. Theory is good for entertainment prior to launch, but after that it's all benchmarking using the hardware and software combination that one plans to use.

Game benchmarks don't belong in a production environment and vice versa.

A surprising result doesn't mean its wrong. Sometimes that's how the dominos fall.

That's why I read Puget Systems tests on their Windows systems. They benchmark by actually using the software in the same manner a professional would and then record and publish the results on their site.
[doublepost=1512215139][/doublepost]Davinci Resolve tests https://www.pugetsystems.com/all_articles.php?tag=DaVinci Resolve

Photoshop hardware recommendations and links to testing results they have done
https://www.pugetsystems.com/recomm...-Adobe-Photoshop-139/Hardware-Recommendations

Premier pro hardware recommendations and test links
https://www.pugetsystems.com/recomm...obe-Premiere-Pro-143/Hardware-Recommendations

They have test articles on hardware use in all kinds of professional software.
[doublepost=1512215401][/doublepost]Obviously there tests are all on Windows machines. But still great reading.
 

theluggage

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Jul 29, 2011
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I see no reason for Apple to remove that function.

The main problem is the 5k display, and the inability of DisplayPort 1.2 to support 5k over a single cable.

On the old 2560x1440 iMacs, the link from the mainboard to the display panel was, essentially, DisplayPort. So it was probably fairly simple to support either an external DisplayPort input, or a DisplayPort signal embedded in a Thunderbolt input.

On the 5k iMac, there is some sort of custom internal display interface. I don't think any details have been published (e.g. is it a full-screen 5k interface, or does it drive the display as two separate sections?) but its easy to imagine why its no longer trivial to just route an external DisplayPort signal to the display. Then, you need two DisplayPort 1.2 cables to drive a 5k screen anyway - or two DP1.2 streams embedded in a Thunderbolt 3 signal (TB1/2 can only extract 1 stream per controller). DisplayPort 1.4 can do 5k, but few things support it (in particular, anything with Intel integrated GPUs or that outputs DP through an Intel Thunderbolt chipset is stuck at DP 1.2a).

So, although it wouldn't be impossible to implement TDM on a 5k iMac, it has turned from what was an easy, cheap-to-add bonus feature into something requiring extensive extra circuitry and connectors.

Still, the inability to use the display for anything else is a major letdown with the iMac.

More constructive suggestion:

If you have desk space, get a 3rd party 27" (4k or 1440p) display and sit it next to the iMac - virtually all such displays have multiple inputs that you can switch between with a couple of button presses on the display. So you could use it either as a second screen for the iMac or the main screen for the cMP.

In the latter case, get Synergy, which will let you seamlessly operate two computers with adjacent screens from the same keyboard and mouse via the network.

Or you could use screen sharing to operate the cMP remotely from your dual-screen iMac - the graphics display would be laggy and artifact-y but if you just wanted to kick off long render jobs, that would be fine.
 

AndreeOnline

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The main problem is the 5k display, and the inability of DisplayPort 1.2 to support 5k over a single cable.

Yes, that makes sense. I guess I had hoped that the special chip Apple developed for the iMac took care of all that. But I think you are right in your analysis.



If you have desk space, get a 3rd party 27" (4k or 1440p) display and sit it next to the iMac - virtually all such displays have multiple inputs that you can switch between with a couple of button presses on the display. So you could use it either as a second screen for the iMac or the main screen for the cMP.

I run a dual 2560x1440 setup now and would need that, or dual 5k, in my next setup. 4k is not an option for me since it's a "lower" resolution (essentially 1920x1080) at 27" or smaller screens, where I'd be using HiDPI mode for hires displays.

The only way an iMac Pro would work is together with a new stand alone Apple display. Each to their own, but I'm not running two different brands of displays side-by-side, personally. I'm not ruling out a new Apple display, but it probably won't show up until the next Mac Pro.

Thanks for your constructive answer anyway!
 

theluggage

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Jul 29, 2011
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4k is not an option for me since it's a "lower" resolution (essentially 1920x1080) at 27" or smaller screens

If you're currently running 2k displays then forget what you know about using "scaled" modes to get non-native resolutions: 4k/5k changes that game completely.

I have a 4k display next to my iMac running in scaled, "looks like 2560x1440" mode, making everything the same physical size as on the iMac - not quite as pin-sharp as the 5k screen of course, and slightly "softer" than the same display in "looks like 1920x1080" mode, but still very usable and way better than a regular 1440p display. And that's just a cheap'n'cheerful 4k display.
 
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AndreeOnline

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…forget what you know about using "scaled" modes to get non-native resolutions: 4k/5k changes that game completely.

Yes, I realise 'scaled' is less of a problem at higher resolutions, but I'm not doing an intermediate monitor swap now before going to 5k. I'll do dual 5k as soon as I find a monitor worth buying and I've ruled the iMac Pro out.
 

PowerMac G4 MDD

macrumors 68000
Mostly because I already have my Mac Pro and some render jobs can run for a few days. It always find it a bit annoying to have one main workstation knowing that when I push 'render', I will be tying up much of the resources of that computer.

When I had a 1080 Ti in my 5.1 and rendered a Maxwell project via GPU, it was very quiet—minded it's own business. Went for days straight with no issues. Same goes for CPU renders, even if it produces a bit more noise (more like a low key humming). The new iMac Pros can be specced to have render grade grunt—at least on the CPU side—but I'm still not convinced it will be happy running for days at a time with 100% CPU utilisation.

I've been very happy with my Mac Pro, so I'm leaning towards waiting for the new one. But I think it will be a very hefty investment to get a new Mac Pro with 18+ cores and dual GPU.

That said, I think the new iMac Pro with a dual eGPU box and some storage would be a pretty able computer.


Ah, I see. Well, do you think that the new-new Mac Pro will cost that much more than the iMac Pro, for a similar configuration? The iMac is a good deal, but it's still—in and of itself—an expensive machine to purchase. If you can afford taking the plunge into buying an iMac Pro, you might be able to do so with the new Mac Pro. Granted, we still have no idea what the new one will necessarily entail.

Also, I WOULD suggest that the iMac Pro may not actually get too noisy if accompanied by an eGPU setup (given that most of the stress is intended for the GPU itself), but I understand what you mean when you say that you'd rather not have your main machine tied up for however long it takes a given task to complete. Though, if I might ask, what do you usually do whilst waiting for your computer to complete a heavy task? If you're not also rendering other things at the same time, wouldn't it make sense to bring smaller tag-along device, such as a phone or laptop? It could even get you away from your desk while your desktop does its thing. Might be beneficial.
 

h9826790

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Ah, I see. Well, do you think that the new-new Mac Pro will cost that much more than the iMac Pro, for a similar configuration? The iMac is a good deal, but it's still—in and of itself—an expensive machine to purchase. If you can afford taking the plunge into buying an iMac Pro, you might be able to do so with the new Mac Pro. Granted, we still have no idea what the new one will necessarily entail.

Also, I WOULD suggest that the iMac Pro may not actually get too noisy if accompanied by an eGPU setup (given that most of the stress is intended for the GPU itself), but I understand what you mean when you say that you'd rather not have your main machine tied up for however long it takes a given task to complete. Though, if I might ask, what do you usually do whilst waiting for your computer to complete a heavy task? If you're not also rendering other things at the same time, wouldn't it make sense to bring smaller tag-along device, such as a phone or laptop? It could even get you away from your desk while your desktop does its thing. Might be beneficial.

I bet the Mac Pro 7,1 will be the most expensive Mac ever.
 

AndreeOnline

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Ah, I see. Well, do you think that the new-new Mac Pro will cost that much more than the iMac Pro, for a similar configuration? The iMac is a good deal, but it's still—in and of itself—an expensive machine to purchase.

Yes, the iMac Pro starting price is already at $4995. Now, this isn't a normal iMac, so you already get 8 cores and Vega 56 at this price + 1TB SSD. But I'd be looking at 10 cores and Vega 64 as minimum and I'd bump the RAM from 32 to 64...

So yeah, that will be the first little surprise we're in for pretty soon: to see what the pricing structure looks like for this new iMac Pro. In classic manner, Apple revealed the iMac Pro saying "a PC build using these components would cost $7000". Note how they didn't say "a PC with similar performance". The reason they get to $7000 is Xeon CPUs and ECC memory.

On the current Mac Pro, going from 8-12 cores is $1200 (one tier up) and from 32 to 64 GB is $800.

I don't think bumping the Vega gfx will be that expensive, but realistically "my" iMac Pro would probably be around $6495—granted, this includes a $1300 display.

And this is what I fear from the Mac Pro: it might be presented as $3495-3995 for a base config, but once you've configured it, you'll be severed the dreaded $12k price tag. Moving up one CPU tier might be $1500 and moving up two tiers might actually be $4000 more...

---------

And yes, I have a 15" MacBook Pro Retina as fallback machine for when the Mac Pro is busy.
 
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AndreeOnline

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I agree. Nothing has changed much in terms of pricing.

I just like to keep repeating it, because for many years a lot of people have been using 12-core Mac Pros for pocket change and modding a 4.1 or 5.1 has been like building a normal, pretty cheap PC. There might be a generation of users who started looking at Mac Pros when the 5.1 was already cheap and they might not realise what the new one will cost in one of the more powerful configurations.

All we can hope for is that Apple really tries to make something worth buying. It's OK for it to be expensive if it's innovative in a good way (like custom chip in 5k monitor or great cooling that makes it silent), but it won't work if it's expensive in a way that Apple RAM always was: same ****, different price.

I'd go as far as saying:

I'd be willing to be forced to use an iMac Pro if the Mac Pro was too expensive, as long as it was generally agreed that the Mac Pro was the pinnacle of workstation design and that the price was motivated by custom solutions—not just markup.

Even if it would piss some people off, I think it would be great for Apple as a brand to show leadership in engineering. Some of the glow of a stellar Mac Pro would always spill over on the iMacs and MacBooks.
 
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whwang

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Dec 18, 2009
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I am thinking about a similar problem. I will get the new iMac Pro, and I want to find a way to keep my current Mac Pro 5,1 running.

The minimum I can do is to just turn the Mac Pro on, remote login to it, and run command-line tasks on it. No graphic interface is involved. This actually works because many of my computations are command-line based. The Mac Pro and the new iMac Pro can connect to a disk array via Thunderbolt (iMac Pro) and 10GbE (Mac Pro) to access the same data. This is a simple way to have more cores running together on some large data, if the nature of the computation allows this kind of parallelization.

It will be even more powerful if I can have access to the graphic interface of Mac Pro on iMac Pro. Unfortunately, as the OP realized, the target display mode does not work. Another possibility is to use VNC. I can use VNC to control to the Mac Pro and access to its OSX graphic interface. My question is, if the Mac Pro is not connected to any monitor, then does VNC still work?
 

h9826790

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My question is, if the Mac Pro is not connected to any monitor, then does VNC still work?

I am very sure it can. Remote control is not necessary mirroring the real display. But anyway, this is super easy to test. Just pull the monitor cable and test by yourself, then you will know "If your setup work".
 

PowerMac G4 MDD

macrumors 68000
I agree. Nothing has changed much in terms of pricing.

I just like to keep repeating it, because for many years a lot of people have been using 12-core Mac Pros for pocket change and modding a 4.1 or 5.1 has been like building a normal, pretty cheap PC. There might be a generation of users who started looking at Mac Pros when the 5.1 was already cheap and they might not realise what the new one will cost in one of the more powerful configurations.

All we can hope for is that Apple really tries to make something worth buying. It's OK for it to be expensive if it's innovative in a good way (like custom chip in 5k monitor or great cooling that makes it silent), but it won't work if it's expensive in a way that Apple RAM always was: same ****, different price.

I'd go as far as saying:

I'd be willing to be forced to use an iMac Pro if the Mac Pro was too expensive, as long as it was generally agreed that the Mac Pro was the pinnacle of workstation design and that the price was motivated by custom solutions—not just markup.

Even if it would piss some people off, I think it would be great for Apple as a brand to show leadership in engineering. Some of the glow of a stellar Mac Pro would always spill over on the iMacs and MacBooks.


I'm aware of the cost of a Mac Pro, BTW. Back when Apple still sold the 5,1, I configured it as high as I could, just to see what the price tag would be. As far as I recall, it was certainly over $10k. I suppose, with the iMac Pro, you get a 5K display with it, plus other things. These are kinds of amenities which custom tower-builders don't understand really contribute to a computer's value.

Well, if you wish, do continue to use the Mac Pro, on the side. Heck, I've still gotten some use out of my 1,1 Mac Pro, simply because it has four hard drive sleds. If I need to quickly wipe a drive, I use it because I don't own an HDD dock. Of course, if it doesn't work out for you, try just connecting a RAID box and eGPU setup to the iMac Pro and also keeping your MBP around as a fallback machine. I would personally enjoy the cleaner setup, lower power usage, and quieter atmosphere. (Well, if the fans on the iMac Pro ramp up, I guess your point, regarding the fans, trumps mine.)
 
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