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MP 1,1-5,1 The most powerful Graphics Card
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Hi Indiox, thanks a lot for your answer.
Do the Radeon VII need extra power than the available from the MacPro? I've heard about some workarounds and I'd not like to do anything but connect it to the PCIe and the two power cables.
Sorry if I forgot to say this.
Do the Radeon VII need extra power than the available from the MacPro? I've heard about some workarounds and I'd not like to do anything but connect it to the PCIe and the two power cables.
Sorry if I forgot to say this.
the native aux power for GPUs (the mini 6 pin connectors) isn't quite enough for the VII. you will need to implement the Pixlas Mod, use 3 available SATA ports, or use an additional PSU
combining the two native aux power mini 6 pins will cover power for one of the 8 pin connectors on the GPU, but you need another ~150w source for the other 8 pin connector too. You can get that through the Pixlas mod, or using 3 SATA ports which is a bit annoying cable wise since you would need to use a dual SATA to 6 pin, and SATA to 6 pin, then combine those two male 6 pins to an 8 pin with a dual female 6 pin to male 8 pin , so at least 3 extra cables required for that method (you may need more "extensions" even because those type of cables are usually pretty short). Or just do something like leave the side cover off or remove a PCIe bracket cover on the rear to snake in the 8 pin cable from a separate PSU. Just remember to turn on that separate PSU prior to powering up the Mac Pro, and to turn off the separate PSU only after the Mac Pro has been shut down. Or use the separate PSU for both 8 pins on the GPU, forgoing the need of the mini 6 pins on the logic board completely
If you don't want to mess around with anything outside of the native mini 6 pins then you need to use a GPU that stays within 225W and uses either no aux power, or a 6 pin, or dual 6 pin, or single 8 pin. This means GPUs with 8 pin and 6 pin, and 8 pin and 8 pin are too power hungry and require additional power
there is a kext solution for a downvolt of the card to use the board connectors.
i still recommend to solve this with the pixlas mod!
forums.macrumors.com
i still recommend to solve this with the pixlas mod!
How to - downvolt a Radeon VII
Just upgraded from RX580 to Radeon VII (it's just $350 from a local seller, like new condition, with 2 years+ warranty. I really can't skip it :D) Anyway, as usual, all AMD GPU are seriously overvolted from factory (Default setting in Wattman shows 1801MHz @1093mV). Properly downvolt the card...
forums.macrumors.com
There is a chance you could get by with a low power version of Vega 56 BIOS in addition to 2x6-pins to 8-pin, with an additional 2xSATA power for that 6-pin connector in your card.
That was a good and thorough enough version of being safe, thank you Skizzo.
Adventurous ones can go ahead and burn their equipment if they want so. Mine is fine still. See link please.
#329
That was a good and thorough enough version of being safe, thank you Skizzo.
Adventurous ones can go ahead and burn their equipment if they want so. Mine is fine still. See link please.
#329
Radeon VII has been discontinued, get a RX 5700 XT for the most powerful GPU available right now. It has a TDP of 225W so you should be able to power it without doing the Pixlas mod, you just need a dual mini 6-pin to 8-pin adapter. https://barefeats.com/cmp-5700-xt-vs-other-gpus.html
Thank you all for your help.
It seems that it will be really messy... unless @jscipione solution.
Touching internal cables, or that kind of workarounds are not for me... As maximum, I thought that buying a psu and connect the cables straight to the card, would be the "cleanest" thing to do... but I don't know if this would work. I should turn on first the external psu and after, the MP. Weird, isn't it?
Will think about it. Thank you all.
It seems that it will be really messy... unless @jscipione solution.
Touching internal cables, or that kind of workarounds are not for me... As maximum, I thought that buying a psu and connect the cables straight to the card, would be the "cleanest" thing to do... but I don't know if this would work. I should turn on first the external psu and after, the MP. Weird, isn't it?
Will think about it. Thank you all.
If Mojave isn't mandatory for you, you should consider the GeForce GTX 1080 too!
It’s about half the price of the Rad VII, beeing not even 10% slower in performance:
...and gets along nicely without any mods to the power supply, just using a dual-mini-6pin to single 8pin cable.
But sadly has drivers only up to High Sierra.
It’s about half the price of the Rad VII, beeing not even 10% slower in performance:
...and gets along nicely without any mods to the power supply, just using a dual-mini-6pin to single 8pin cable.
But sadly has drivers only up to High Sierra.
You could also try a Quadro K6000. There are some benchmarks in this thread that suggests it rivals a GTX 1080 Ti in professional apps and it has two 6-pin connectors so it should work just fine in a 5,1 with no power mods. RX 580 is probably fine for AMD.
egpu.io
2015 13" MacBook Pro [5th,2C,U] + Quadro K6000 @ 16Gbps-TB2>...
System specs -MacBook Pro 13 inch 2015, i7-5557U 2-core, 16GB Ram, 512GB SSD -iGpu Intel Iris Graphics 6100 -External Monitor Samsung 2560x1440 -...
egpu.io
For FCPX, AMD works so much better, Radeon VII sure will kill all Nvidia GPU.
the RX 5700 XT is a 6pin + 8pin GPU and needs to have both powered. yes, it is supposed to keep wattage under 225W but what you suggested would leave the 6pin connector without a proper cable connected. it will cause issues
the OP still need to implement one of the three additional power methods I mentioned in my previous post if using a RX 5700 XT
No, do not take that advice from them, the RX 5700 XT still needs to have both its 6pin and 8pin connectors properly connected and powered (I highly doubt you want to get into undervolting, and/or underclocking, and/or allocating how the power is drawn from the mini 6pins vs the PCIe slot in order to save yourself like $5 on a cable and 5 mins of installation time)
I detailed the separate PSU method in my previous post. I used a separate PSU solely, a separate PSU to power just the 6pin while the 8pin was powered by both the internal mini 6pins, I also used a dual SATA to 6 pin to power the 6pin while the 8 pin was powered by both the internal mini 6pins. They are all appropriate and safe methods for a 6+8pin GPU such as the RX 5700 XT
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I overlooked that, good point! lol
In that case the VII is the most powerful GPU for Mojave. if they want to use the Catalina patcher they could update to Catalina. My experience with the RX 5700 XT worked poorly on 10.15.1 but cleared up any issues I had since 10.15.2
Your Aorus model is one of those "on steroids" GPU versions with factory OC. It's more powerful enough they apparently had to make it 8+8pin instead of just 6+8pin. I just had to look this up thinking the TDP would be higher too....but its the same 225W.....I don't quite understand how all that works. I would think it would be because the OC needs more W but I guess not. I suppose it may be something to do with where power is drawn from, mini 6pins vs PCIe slot.
I don't have an RX 5700 XT so take this with a grain of salt, but in the barefeats article I linked to https://barefeats.com/cmp-5700-xt-vs-other-gpus.html it says:
"Because the RX 5700 XT TDP rating is 225W, we were able to run it using only the factory PCIe bay power feeds. With the help of HWMonitor, we plotted the draw of the GPU slot plus the two factory power feeds. The RX 5700 XT reported a max of 201W. The RX 580 reported even higher at 215W. The Radeon VII was fed extra power from an external PSU since its TDP is 300W."
Of course you'll need Catalina to run this card as it's the minimum version of macOS that provides drivers for the RX 5700 XT.
While 225W is the correct TDP for RX 5700XT, this not make it a compatible GPU for MP5,1. Even the so common AMD RX 580 has models that when in full load shutdown a MP5,1.
The time that PC GPUs balanced the power draw is long gone, it ended with RX 480 OEM/AMD reference model. At best, a RX 5700XT will draw around 35W from the PCIe slot and then ~190W from the two PCIe AUX power connectors, but this power draw is not equally divided/equalised between the two backplane connectors.
So, seems reasonable that ~190W would be inside the power capabilities of the backplane, ~95W from each PCIe AUX boost connector, but it's not so simple since, while the backplane power cut is around 120W for each PCIe AUX power connector, modern GPUs can have momentous spikes of more than that. That's the problem.
The rule for MP5,1 GPU usage is always to balance the power draw and if you don't want to do a Pixla's mod or use external PSU, only use GPUs that always fit the power envelope. Today, the faster GPU that fits is VEGA 56 with the power saving ROM.
People really need to stop thinking that PCIe slot 75W + PCIe AUX A 75W + PCIe AUX B 75W = 225W GPU. It's definitively not.
VEGA 56 and 64 cards have a double firmware, selectable by a switch, with normal and power saving settings. See here https://hexus.net/tech/reviews/graphics/108889-amd-radeon-rx-vega-64-radeon-rx-vega-56/?page=3
These are the switch settings for a reference model, non-OC, VEGA 56:
- With the normal setting is 165W + 50% PowerTune (max ~247,5W).
- With the 25% power saving setting enabled, Vega 56 is 122W + 50% PowerTune (max ~183W).
I think that the safest way is to buy a reference model VEGA 56 and use an eVGA PowerLink and two standard mini-PCie 6pin cables to feed power the GPU. This way you will balance the power consumption between both PCIe AUX A and B simultaneously and always keep the power draw inside the safety parameters of the backplane power plane.
Please note that VEGA 56 non reference models usually use the NANO PCB design and you can't connect an eVGA PowerLink without mods. Save yourself lot's of trouble and only buy a VEGA 56 with the AMD reference layout.
TechPowerUp reference post about VEGA 56 lists the models that use the reference design:
AMD Radeon RX Vega 56 Specs
AMD Vega 10, 1471 MHz, 3584 Cores, 224 TMUs, 64 ROPs, 8192 MB HBM2, 800 MHz, 2048 bit
Edited to show the real ROM switch and not the GPU tachometer one.
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Who makes ref models nowadays? The usual guys? (MSi, Sapphire, Gigabytes?)
On a similar question in another thread, I was told Radeon VII is probably the last 4,1/5,1 update before going for a Hackintosh or a MacPro 7,1 in terms of power
I think that no one is making VEGA 56/64 GPUs nowadays, you'll only find NOS or used cards. For the manufacturer, this is very regional and the reference cards that I find for sale down here will be different from what you will find locally. The best bet is to open the TechPowerUp VEGA 56 page and see all models that use the AMD reference design and try to find one for sale on your regional market. TechPowerUp reference post about VEGA 56 lists the models that use the reference design:
AMD Radeon RX Vega 56 Specs
AMD Vega 10, 1471 MHz, 3584 Cores, 224 TMUs, 64 ROPs, 8192 MB HBM2, 800 MHz, 2048 bit
Any high end GPU newer than VEGA 56 is over the power envelope of MP5,1 without Pixla's mod, see my previous posts where I explain the motives.
Radeon VII is a lot more powerful than VEGA 56/64 and works perfectly with Mojave, while RX 5700/5700XT needs Catalina and for some applications will be a lot slower than VII. Some users can get the RX 5700XT working with MP5,1 without Pixla's mod, but I don't think that is a sane choice. Don't ever run a RX 5700XT at full load without Pixla's mod or external GPU, you will need a backplane replacement down the road.
MP5,1 will continue to work with newer GPUs while 10.15
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Thanks that's great advice. At the moment, second hand Vega 56 GPUs are in the 200€ price point which is pretty fair as it's an improvement over the RX580 for a decent price. Radeon VII are still in the 600€ region (second hand), which is a lot more money, but a lot more power. There is no hurry though, so those will drop in price slowly I hope.
Catalina being officially a no-no for cMP, relying on it might be a bit risky when you use it a production machine and not a hobby. Also, there comes a point when the GPU power is also castrated by a CPU that can't cope. Radeon VII is probably the sweet spot.
Catalina being officially a no-no for cMP, relying on it might be a bit risky when you use it a production machine and not a hobby. Also, there comes a point when the GPU power is also castrated by a CPU that can't cope. Radeon VII is probably the sweet spot.
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I can see a new Radeon VII at 599€ (incl. 24%VAT) in my country. I am a little bit tempted, it would make me a reasonable TwinMotion machine out of my 5.1, for a year or two I think. I've got on of those aformentioned Vega 56 cards (PowerColor Red Dragon, switch at low bios mode) now, and it's good enough, I am quite happy with it. But the memory limit comes in to play sometimes (8GB). 16GB would be ideal for my projects as of now. It would need external power or Pixla's mod. Or, if I remember it right, you could make a mod to the powertable/bios and run it from the orig. PSU (search for h9826790 posts).
While Powertable hacks helps limiting the power usage of a Radeon VII, the spikes of power consumption will continue.
Use a Radeon VII without Pixla's mod or external PSU and you will need a backplane replacement soon, MP5,1 power plane was not made for this kind of GPU load, it's a 2nd half of 2008 design…
For anything that needs more power than a VEGA 56, do a Pixla's mod.