MP 7,1 Stable Diffusion on 7,1 Mac Pro, or just build a PC?

[Z28McCrory]

Hi Everyone,

I'm a photographer who recently went down the AI rabbit hole and would like to start using Stable Diffusion. It appears there are a lot of road blocks to run it on a 7,1 Mac Pro. As a short term solution I'm renting GPU time on a remote install via a Web UI, but I'd love to find a way to run it locally. Specifically the Automatic1111 GUI.

I've been able to run it locally using CPU only (Not with Automatic1111, but with other GUI's), but that's brutally slow. Also after using Automatic1111 on the remote server, it seems very limiting to use any other GUI.

My first idea was to simply throw a 4090 in my 7,1 and use my Bootcamp Windows install that I use for gaming, but it seems there are some physical power restrictions and some other major issues (needing to disable the AMD GPU every time, etc). My other idea was to upgrade my 16" MacBook Pro (intel) to a new M2 Max, but I'm not sure its worth the cost to upgrade considering I love my laptop for every other application, and the M2 Max still isn't going to achieve anywhere near the performance of a 4090.

Looking for advice from the fine folks on this forum. Is there a simple way to do this with my 7,1 or is it just a headache waiting to happen.

Thanks for your time.

 

[prefuse07]

There are quite a lot of folks successfully using the 4090 in the 7,1 running in Windows, i've even seen posts on here of people running DUAL A5000's in their 7,1

Will try to find that thread and update this post for you.

Update: HERE is the thread <-- check out page 17, but you might want to start from 18 and just back track.

 

[Z28McCrory]

There are quite a lot of folks successfully using the 4090 in the 7,1 running in Windows, i've even seen posts on here of people running DUAL A5000's in their 7,1

Will try to find that thread and update this post for you.

Update: HERE is the thread <-- check out page 17, but you might want to start from 18 and just back track.

Thanks for the link to that thread.

It looks like people have physically put them in there, but after 18 pages of reading I'm still struggling to understand a few things:

1) Does the 4090 need to have the monitor plugged into it, or could I just chose that as the compute GPU.

2) Does this cause any issues when I'm in regular Mac OS. I briefly had a pair of Radeon VII's in my 7,1 and there was an issue where the fans would go full blast if the computer went to sleep. It sounds like there may be a similar issue with the nVidia cards where the computer can crash if it goes to sleep or even if the monitors turn off.

3) Will Stable Diffusion not run on any AMD cards at all, or just not my Vega II? And if SD can run on a modern AMD card, is there anything that's even in the same ballpark as the 4090. I'm ok with sacrificing some performance in exchange for a more user friendly card that doesn't require me to use a bunch of workarounds to make it work.

 

[prefuse07]

Thanks for the link to that thread.

It looks like people have physically put them in there, but after 18 pages of reading I'm still struggling to understand a few things:

1) Does the 4090 need to have the monitor plugged into it, or could I just chose that as the compute GPU.

I believe you would need to be plugged into the 4090 if you wanted to use it as your video output device, but then you would need to plug back into your MPX module or an AMD GPU when going back into macOS.

2) Does this cause any issues when I'm in regular Mac OS. I briefly had a pair of Radeon VII's in my 7,1 and there was an issue where the fans would go full blast if the computer went to sleep. It sounds like there may be a similar issue with the nVidia cards where the computer can crash if it goes to sleep or even if the monitors turn off.

3) Will Stable Diffusion not run on any AMD cards at all, or just not my Vega II? And if SD can run on a modern AMD card, is there anything that's even in the same ballpark as the 4090. I'm ok with sacrificing some performance in exchange for a more user friendly card that doesn't require me to use a bunch of workarounds to make it work.

As to these questions, I am paging @Matty_TypeR as I believe he uses a 4090 FE with his 7,1 and can probably provide better guidance here.

 

[h9826790]

3) Will Stable Diffusion not run on any AMD cards at all, or just not my Vega II? And if SD can run on a modern AMD card, is there anything that's even in the same ballpark as the 4090. I'm ok with sacrificing some performance in exchange for a more user friendly card that doesn't require me to use a bunch of workarounds to make it work.

Stable Diffusion definitely can run with AMD cards or in macOS. However, many advance functions will be missing. Also, the performance will be way behind what Nvidia GPU can do (due to almost everything in Stable Diffusion is base on CUDA to optimise).

If you want to learn Stable Diffusion seriously. I suggest you just get a PC with 4090. No monitor need to connect to that PC. Just run it as the local Stable Diffusion server.

Then you can use MS remote desktop to control that PC on your 7,1. And simply use the browser on your 7,1 to use the Automatic1111 web UI.

 

[Z28McCrory]

Thanks for the replies everyone. I’m a little further down the rabbit hole.

It seems the 4090 Founders Editions makes the most sense, as the size and the cooling play well in the 7,1 (everything I’m saying here is from what I’ve read, so please feel free to jump in if it’s inaccurate).

I’m running a pair of LG 4K monitors that are pretty basic. They have dual inputs. I’m using the DisplayPort on both of them. If I have a 2nd GPU for Windows, I’m thinking I can simply use the HDMI inputs and they’ll automatically switch over based on how I boot? This is assuming I disable the Vega II in Windows BC so the 4090 is the only active GPU.

Assuming this all is correct, is the only downside in MacOS, is that once the 4090 is installed I need to prevent the computer from going to sleep?

h9826790 -​

I like the idea of running a SD server and accessing it like you recommend. It would be a bit of a learning curve for me, because it’s been years since I attempted something like that, but perhaps that’s a phase 2 plan once I tinker with the 4090 in my BC install. I can certainly see the utility in being able to access a local SD server from my laptop while sitting on the couch away from my main computer, etc. And it’s only taken me a couple days of tinkering with SD to realize that anything short of Automatic1111 (With Control Net, etc) is extremely limiting.

​

 

[Matty_TypeR]

I run a 4090 ref card in my mac pro 7.1 in windows. it is powered via an external corsair SF-750w PSU which i have a switch on to power it. the cable which is a corsair 4090 cable is slim, flat and long enough that the PSU sits under the bench top of where Mac pro 7.1 sits and the 4090 cable comes through the PCIe slot at back.

When in Mac OS be it Monterey or Ventura the PSU for the 4090 is powered off. OSX run's perfectly and 100% stable. In windows 11pro i turn on the 4090 PSU and it boots straight into windows again no issues. I do disable the 6900xt in windows.

This combination has worked flawless for the last 3 to 4 months with no issues. the 4090 is a monster card in windows and although the 7.1 is a little CPU limited it still way out performs the 6900xt in windows.

I will be looking to upgrade the 6900xt to a 7900xtx if and when supported in OSX but in windows the 4090 is just epic.

 

[Z28McCrory]

I run a 4090 ref card in my mac pro 7.1 in windows. it is powered via an external corsair SF-750w PSU which i have a switch on to power it. the cable which is a corsair 4090 cable is slim, flat and long enough that the PSU sits under the bench top of where Mac pro 7.1 sits and the 4090 cable comes through the PCIe slot at back.

When in Mac OS be it Monterey or Ventura the PSU for the 4090 is powered off. OSX run's perfectly and 100% stable. In windows 11pro i turn on the 4090 PSU and it boots straight into windows again no issues. I do disable the 6900xt in windows.

This combination has worked flawless for the last 3 to 4 months with no issues. the 4090 is a monster card in windows and although the 7.1 is a little CPU limited it still way out performs the 6900xt in windows.

I will be looking to upgrade the 6900xt to a 7900xtx if and when supported in OSX but in windows the 4090 is just epic.

Can I ask why you’re powering it with external PSU? Could the 7,1 power supply not keep up, was it for other reasons?

 

[Matty_TypeR]

The main reason to power it from external PSU is the 4090 would need 4 X 8pin PSU connections from the Main board to be powered. thats all the 8 pin connection's available on the main board apart from 1x 6 pin connection. my 6900xt requires 3 X 8 pin connections via the main board so no way i could power both cards internally.

Plus switching off the 4090 when in Mac OSX made sense to save any conflicts.

 

[elmon]

You can run most of the diffusion models with https://drawthings.ai/ . It's free, but not open source. If you want to learn and experiment, there is https://github.com/madebyollin/maple-diffusion , but it's more of a proof-of-concept, so the code is pretty messy and may not be well optimised.

 

[Z28McCrory]

The main reason to power it from external PSU is the 4090 would need 4 X 8pin PSU connections from the Main board to be powered. thats all the 8 pin connection's available on the main board apart from 1x 6 pin connection. my 6900xt requires 3 X 8 pin connections via the main board so no way i could power both cards internally.

Plus switching off the 4090 when in Mac OSX made sense to save any conflicts.

Thanks for the explanation. Right now I only have a Vega II MPX installed, so I assume I’ll be OK to pull power from all the 8 pins on the motherboard and not need the external PSU?

Have you tried booting into Mac OS with the 4090 powered on? I’m just curious if it causes any conflicts (other than the common one I read about with not being able to let the computer go to sleep

You can run most of the diffusion models with https://drawthings.ai/ . It's free, but not open source. If you want to learn and experiment, there is https://github.com/madebyollin/maple-diffusion , but it's more of a proof-of-concept, so the code is pretty messy and may not be well optimised.

I did try out Drawthings on my M1 IPad just to experiment. It was fun to try, and I did download some models from Cititai to play with.

Once I saw the power of Controlnet 1.1 with Automatic1111 though, it kinda ruins every other UI without it. Controlnet takes it from being a fun toy, to being a powerful tool that I can implement into my photography.