MP All Models AMD Radeon RX 6800 XT / 6900 XT for macOS?

[CNDCodewarrior]

Just installed a Gigabyte RX6900XT OC 16 gig

GIGABYTE RX 6900 XT GAMING OC 16G

GIGABYTE RX 6900 XT GAMING OC 16G

www.amazon.ca

Install went fine, no size issues, here's a couple of photos. No bench's yet and don't think I need to do them for you guys as there are many already.

Used the iPhone 12 to measure the space so take it with a grain of salt.

Happy card hunting for those still looking.

 

[fedism]

From what I've seen, there are multiple reports of Big Navi not working on 5,1s, and no reports of it working. If there is a config working, no one has reported it yet.

And because Apple is no longer producing firmware updates, no versions of Big Sur (or Monterey) are going to fix.

Thanks. I am running the latest firm ware 1.44 and will keep a close eye open core late bloom fixes to see if compatibility arises.

 

[tsialex]

Thanks. I am running the latest firm ware 1.44 and will keep a close eye open core late bloom fixes to see if compatibility arises.

This will not be solved with OpenCore/Latebloom or anything else, it's on a level below.

When a NAVI 2x GPU is present on a MacPro5,1, the Mac Pro won't even power on to the firmware POST, so the incompatibility happens long before loading OpenCore or any other boot loader.

Btw, some datacenter AMD GPUs now require AVX and I wouldn't be surprised that the NAVI 2x optionROM could be incompatible with Westmere Xeons.

 

[joevt]

This will not be solved with OpenCore/Latebloom or anything else, it's on a level below.

When a NAVI 2x GPU is present on a MacPro5,1, the Mac Pro won't even power on to the firmware POST, so the incompatibility happens long before loading OpenCore or any other boot loader.

Btw, some datacenter AMD GPUs now require AVX and I wouldn't be surprised that the NAVI 2x optionROM could be incompatible with Westmere Xeons.

Is POST before or after UEFI?
What if a normal GPU is installed in slot 1 and the Navi 2x is in a different slot or a PCIe expansion box?
If we could get Thunderbolt hot plug, then maybe it could work as an eGPU since in that case the GPU firmware would not be used during UEFI.
If it's an AVX issue, then I wonder if an instruction emulator can be added to UEFI (like AAAMouSSE except for UEFI and AVX)? You would need a way to make that load before the GPU firmware.

I guess the first thing to try might be to patch the GPU firmware. First, try to just no-op the gop.

 

[tsialex]

Is POST before or after UEFI?

Before.

What if a normal GPU is installed in slot 1 and the Navi 2x is in a different slot or a PCIe expansion box?

AFAIK, everyone that tested a NAVI GPU also tried with an AppleOEM GPU present to see if it would work, none got it working.

If we could get Thunderbolt hot plug, then maybe it could work as an eGPU since in that case the GPU firmware would not be used during UEFI.
If it's an AVX issue, then I wonder if an instruction emulator can be added to UEFI (like AAAMouSSE except for UEFI and AVX)? You would need a way to make that load before the GPU firmware.

I guess the first thing to try might be to patch the GPU firmware. First, try to just no-op the gop.

Since with a NAVI GPU present the Mac Pro wouldn't past POST, maybe the next test that should be done is with an eGPU. Not much practical or economical sense, but maybe will give some clues.

Btw, I searched all major hackintosh sites when I looked at this issue, at the time no one reported a NAVI GPU working with a Westmere Xeon and the oldest hack that I read about was Xeon E5-V4 from the Broadwell-EP family.

 

[DISTRESS0R]

Hello, I just ordered the w6800x MPX module for my Mac Pro 7.1 12 core 48gb Ram system. I currently am using the w5700x MPX module. Are there any specific tests you all would like to see in relation to these specific cards? Happy to share, as I'm not seeing this sort of info elsewhere on the web 2.0

 

[Grilled Cheese]

Hello, I just ordered the w6800x MPX module for my Mac Pro 7.1 12 core 48gb Ram system. I currently am using the w5700x MPX module. Are there any specific tests you all would like to see in relation to these specific cards? Happy to share, as I'm not seeing this sort of info elsewhere on the Web 2.0

Anything in Final Cut Pro would be very interesting - especially how it quickly it performs background rendering tasks such as colour adjustment, stabilisation etc. Export times seem to be the most commonly tested function, but I’m more interested to see how well it improves performance during editing. Thank you!

 

[skippermonkey]

Hello, I just ordered the w6800x MPX module for my Mac Pro 7.1 12 core 48gb Ram system. I currently am using the w5700x MPX module. Are there any specific tests you all would like to see in relation to these specific cards? Happy to share, as I'm not seeing this sort of info elsewhere on the web 2.0

I just pulled the trigger on the Duo for rendering in Octane and C4D. I have a couple of 5700XTs but the main bottleneck is the 8GB VRAM – amazing how quickly it fills and causes Octane to choke up. Anyone need a second 580X MPX?

 

[flowrider]

Hello, I just ordered the w6800x MPX module for my Mac Pro 7.1 12 core 48gb Ram system. I currently am using the w5700x MPX module. Are there any specific tests you all would like to see in relation to these specific cards? Happy to share, as I'm not seeing this sort of info elsewhere on the web 2.0

Another thread is dedicated to the MPX W6800.

https://forums.macrumors.com/thread...s-vs-vega-ii-duo-2x-w5700x-2x-6900xt.2307050/

This is not the place for those discussions. This thread is dedicated to the RX6800 models.

Lou

 

[randy85]

Hello, I just ordered the w6800x MPX module for my Mac Pro 7.1 12 core 48gb Ram system. I currently am using the w5700x MPX module. Are there any specific tests you all would like to see in relation to these specific cards? Happy to share, as I'm not seeing this sort of info elsewhere on the web 2.0

Yes! Could you try rendering out of Resolve a challenging 4k sequence with both GPUs and then just the more powerful W6800X on its own?

I have my W5700X with a 6800 XT and have found that performance in Resolve is better when I deselect the W5700X for compute and just use it for display (I have a Pro Display XDR so need to keep it to run that).

I think it would be useful to get more real life results to see if running two mismatched GPUs is detrimental.

 

[DISTRESS0R]

Anything in Final Cut Pro would be very interesting - especially how it quickly it performs background rendering tasks such as colour adjustment, stabilisation etc. Export times seem to be the most commonly tested function, but I’m more interested to see how well it improves performance during editing. Thank you!

Might have to get myself a copy of Final cut (finally!) Currently using Resolve

 

[DISTRESS0R]

Yes! Could you try rendering out of Resolve a challenging 4k sequence with both GPUs and then just the more powerful W6800X on its own?

I have my W5700X with a 6800 XT and have found that performance in Resolve is better when I deselect the W5700X for compute and just use it for display (I have a Pro Display XDR so need to keep it to run that).

I think it would be useful to get more real life results to see if running two mismatched GPUs is detrimental.

Absolutely! Just waiting on my shipment to arrive, probably will be a couple more weeks from Shanghai

 

[flowrider]

Is this coming❓

Lou

 

[diamond.g]

Is this coming❓

View attachment 1826056

Lou

These golden sample units will be interesting to run with. From what I have heard they get an additional 50W TGP over the normal 6900XT. Still not quite enough memory bandwidth to catch up to the 3090 in high resolution situations.

 

[elgargui]

6900XT works fine with my cat and MP

 

[avkills]

I like your supports. ??

 

[LEOMODE]

Hello,

Would this support Mac Pro 7,1 length-wise? I'm not sure how long this is...I do think this is a reference card..?

 

[DFP1989]

Hello,

Would this support Mac Pro 7,1 length-wise? I'm not sure how long this is...I do think this is a reference card..?

View attachment 1836015

The reference cards were well under 300mm so yes.

 

[LEOMODE]

I ran dual 6900xt - was perfectly fine and stable in FCP and Resolve, fairly quiet too.
if I didn’t know what was in the Mac Pro, I would not be able to tell the difference between these GPUs and an mpx module.

Hey, just curious, so without any default MPX module, at least for now, you're saying everything performs/boots/safe-modes just fine with the non-MPX card right?

 

[LEOMODE]

The reference cards were well under 300mm so yes.

Thanks for the fast reply. Helps.

 

[flowrider]

Hey, just curious, so without any default MPX module, at least for now, you're saying everything performs/boots/safe-modes just fine with the non-MPX card right?

Yes. Everything works as it should. You do need 2 four pin to four pin cables however. Some third party RX6900XT cards require 3 cables, but not the one you have pictured which is a reference card.

Note I am running a Gigabyte RX6800XT a non-reference card.

Belkin AUX Power Cable Kit for Mac Pro - Apple

Apple Store Search Results

www.apple.com

Lou

 

[LEOMODE]

Yes. Everything works as it should. You do need 2 four pin to four pin cables however. Some third party RX6900XT cards require 3 cables, but not the one you have pictured which is a reference card.

Note I am running a Gigabyte RX6800XT a non-reference card.

Belkin AUX Power Cable Kit for Mac Pro - Apple

Apple Store Search Results

www.apple.com

Lou

Thanks, I do already have that because I also have RTX3090 in my Mac Pro. I remember when I first got my Mac Pro back in early 2020, 6000 series didn't come out at the time so there was no clarity whether non-MPX module would work just like MPX module, but it looks like other than buying it from Apple, at least the current OS works fine.

 

[flowrider]

^^^^Big Navi works fine in Big Sur on 11.4 and up. And on Monterey.

Lou

 

[LEOMODE]

What's the most recommended 6900XT card at the moment? I just see a reference card and Barefeats said he got a Sapphire Nitro+ one. Just wondering what would be the most reliable (first and foremost) and performant one.

 

[flowrider]

^^^^Go back and review Page 29 of this thread. Here's one of the posts from P29 that looks at sizes and the poster's Gigabyte RX6900XT cards:

Finally got a working card. I got an exchange for a Gigabyte RX 6900XT Gaming OC, which is 29cm so there's a bit of clearance, which I prefer vs the Sapphire which is just 31cm.

Below are my updated notes as to which card should work, some basic benchmarks and usage notes.

Card has to be <= 310mm to fit. 31cm is the absolute max, keep in mind graphic card manufacturer have no problem miss-labelling by a cm or two.

Benchmarks (all Geekbench 5.1.0 Metal):

• MPX 580X (for reference): 47234
• Gigabyte RX6900XT Gaming OC 16GB: 187686 (cabled plugged directly in RX6900XT), 173579 (display plugged in MPX 580X)
• MPX W6800X (Single card): 144910 (https://forums.macrumors.com/thread...s-vs-vega-ii-duo-2x-w5700x-2x-6900xt.2307050/)
• Radeon VII: 58491 (https://barefeats.com/rx-6900-xt-vs-other-gpus-in-imac-pro.html)
• RX 5700 XT: 71203 (https://barefeats.com/rx-6900-xt-vs-other-gpus-in-imac-pro.html)
• Pro Vega 64: 62326 (https://barefeats.com/rx-6900-xt-vs-other-gpus-in-imac-pro.html)
• RX6800 Vanilla card: 141,703 (https://forums.macrumors.com/thread...s.2262295/page-24?post=30121368#post-30121368)

Usage notes, with MPX 580X & 6900XT in the Mac Pro:

• To use the 6900XT with an app that does not support GPU selection you need to plug the display cable directly in the GPU and run that app on the monitor. That can be done while the Mac Pro is running.
• Apps that support gpu selection work seamlessly, just select the GPU you want to use.
• It looks like there's a ~8% perf advantage if you plug the display cable directly in the RX6900XT. Not too sure why that applies to compute only usages, but GB5's benchmark shows a difference.

Fits (tested / seen working):

• Reference RX 6800 / 6900 XT are 267mm and fit easily.
• Gigabyte Radeon RX 6800 XT & RX 6900 XT GAMING OC 16G: L=286 W=118 H=58 mm. That's what I have. (https://forums.macrumors.com/threads/amd-radeon-rx-6800-xt-6900-xt-for-macos.2262295/post-30169771)
• Sapphire Nitro+ RX 6800/6900XT. Non special edition, that is important, SE does not fit, the non-SE that fits is 310mm which is at the absolute limit of what will fit in. (https://forums.macrumors.com/threads/amd-radeon-rx-6800-xt-6900-xt-for-macos.2262295/post-30163090)

Should fit (but didn't see first hand):

• Gigabyte Radeon RX 6800 XT & RX 6900 XT 16G: L=267 W=120 H=49 mm, should fit
• ASRock RX 6800 Challenger Pro: 305x131x55mm, might just fit

Does not fit:

• Sapphire Nitro+ Special Edition RX 6800/6900 XT, advertised as 310mm but is in fact 320mm. The non-se version is in fact 310mm and does fit.
• PowerColor Radeon RX 6800 XT - Red Devil: 320mm*135mm*62 mm: https://forums.macrumors.com/threads/amd-radeon-rx-6800-xt-6900-xt-for-macos.2262295/post-29751958
• ASROCK RX 6800 XT is huge and does not fit. (https://forums.macrumors.com/threads/amd-radeon-rx-6800-xt-6900-xt-for-macos.2262295/post-30164008)
• Asus Tuf Gaming RX 6800/6900 XT: 32 x 14.02 x 5.78 Centimeter.
• AORUS Radeon™ RX 6800 XT AORUS MASTER TYPE C 16G: L=324 W=140 H=60 mm

Pics of the Gigabyte RX6900XT Gaming OC in the Mac Pro:
View attachment 1818168

View attachment 1818170

Lou