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EugW

macrumors G5
Jun 18, 2017
14,897
12,866
Many suggest in their MacPro1,1 flashing tutorials that you should put the original card back into the machine to do the MacPro2,1 and SMC flashes. I didn't bother swapping in my 7300 GT, since my Radeon 5770 Mac version works fine on that machine at boot up even in Lion. The flashes worked fine with the 5770 in place.
 

unpapapro

macrumors newbie
Apr 30, 2020
22
7
Quebec City, Canada
Many suggest in their MacPro1,1 flashing tutorials that you should put the original card back into the machine to do the MacPro2,1 and SMC flashes. I didn't bother swapping in my 7300 GT, since my Radeon 5770 Mac version works fine on that machine at boot up even in Lion. The flashes worked fine with the 5770 in place.

simply because what i requested - if you read well - is to have a EFI based card... which the 5770 is... :)
 
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EugW

macrumors G5
Jun 18, 2017
14,897
12,866
simply because what i requested - if you read well - is to have a EFI based card... which the 5770 is... :)
Yes I read something about that earlier.

I am a posting just to confirm this for anyone a little concerned by those tutorials’ warnings.
 
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ri2nonerok

macrumors newbie
Jul 24, 2020
5
0
DUAL GPU FOR MP 5,1

Hello all,
Has anyone had any luck with successfully using a dual GPU setup for Mojave or Catlina with 2 different Radeon Gpu's?

I own an R9 280x and now a Vega 56 both flashed.

Going to swap it out when I can but first wanted to know if anyone had success or issue if anyone even did this before.

Thanks!
 
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ri2nonerok

macrumors newbie
Jul 24, 2020
5
0
You need additional power just to power the Vega 56.
Hmm Interesting, than you. This is the first time I read up on it.
Nonetheless, I suppose I would have to do a powersuppy mod. In theory is it possible to run dual radeon EFI GPUs although they are not the same model?

EDIT: Perhaps I misread this post, I so have a cable that will use the Vega 8pin setup that was included for more power connectivity.
 
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MarkC426

macrumors 68040
May 14, 2008
3,693
2,096
UK
Refer to page 1.
It tells you what you need for certain gpu’s.
Different manufacturers have different connectors, some have 8pin, some 6+8pin.
 

ri2nonerok

macrumors newbie
Jul 24, 2020
5
0
Thank you MarkC but I do have some items to look over for powering up the video card. My main topic I wanted to bring up while I wait for the video card is the possibility and functionality of running R9 280X EFI along with a VEGA 56 EFI, or any dual efi GPU setup thay are not the exact same model. If so, what would be the steps to do so?

Im sure theres at least one other person whom was upgraded their r9 280x gpu and has considered just adding that old r9 along with their upgraded eif gpu for a 5,1.
 

jvlfilms

macrumors 6502
Dec 11, 2007
269
231
Staten Island, NY
So currently I have a Sapphire Radeon RX 580 which I'm very happy with - it's powered by an 8pin to dual 6 pin adapter.

I was entertaining the idea of potentially adding a second card to my 4,1->5,1, which I don't think is possible given the power requirements of this card.

Without doing a Pixlas mod, is something like this even possible? I could use additional power from my SATA optical drives since I rarely use those anyway.
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
So currently I have a Sapphire Radeon RX 580 which I'm very happy with - it's powered by an 8pin to dual 6 pin adapter.

I was entertaining the idea of potentially adding a second card to my 4,1->5,1, which I don't think is possible given the power requirements of this card.

Without doing a Pixlas mod, is something like this even possible? I could use additional power from my SATA optical drives since I rarely use those anyway.
You can use SATA ports.

Or you can simply downvolt the RX580, which can make it draws noticeably less power, and able to be powered by a single mini 6pin (except Furmark).


However, this mod will disable the GOP, which means, you card can no longer display boot screen via OpenCore.
 
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jvlfilms

macrumors 6502
Dec 11, 2007
269
231
Staten Island, NY
You can use SATA ports.

Or you can simply downvolt the RX580, which can make it draws noticeably less power, and able to be powered by a single mini 6pin (except Furmark).


However, this mod will disable the GOP, which means, you card can no longer display boot screen via OpenCore.


Thanks for the quick reply. I use Windows quite frequently so the idea of having boot screens is more important than the second GPU in my current setup.

But is it possible to undervolt one card and leave the other stock? That way I could power it from the SATA connections + PCIE port itself.

Or do you think that the second card could be powered sufficiently by the SATA ports without undervolting?
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Thanks for the quick reply. I use Windows quite frequently so the idea of having boot screens is more important than the second GPU in my current setup.

But is it possible to undervolt one card and leave the other stock? That way I could power it from the SATA connections + PCIE port itself.

Or do you think that the second card could be powered sufficiently by the SATA ports without undervolting?
Possible, SATA ports rated ~55W. So, you can power a 8pin by 3x SATA ports.
 
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jvlfilms

macrumors 6502
Dec 11, 2007
269
231
Staten Island, NY
Possible, SATA ports rated ~55W. So, you can power a 8pin by 3x SATA ports.

Thanks, for right now my setup is perfect but this info will be useful in the future.

For a duo RX580 set-up, many members here would just advise you the Pixla Mod. The beauty of Pixla mod is you draw power directly from the main source, the least impact to performance of other parts.

I agree, and it doesn't seem that hard but I'm scared to mess with my power supply. Maybe in the future my mindset will change but we'll see!
 

sanfrancisofont1984

macrumors regular
Aug 5, 2020
237
67
I would be curious to see compatibilities of Radeon Pro WX 9100 and AMD Radeon Pro VII, esp. if their prices drop to an affordable level in the future.

On paper they seem to have these advantages:
  • Pro features (I cannot pin point anything specific but I suppose it is a more is better situation)
  • Relatively conservative in terms of power consumption.
  • Small number of SKUs around.
 
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Hdalio

macrumors newbie
Jun 5, 2019
21
4
Downgrade the driver to V378.

V387 drivers aren't good for multi GPU.


Thanks h9826790
its working, but there are still some problems, crash and logoff suddenly, black stripe on finder!
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Thanks h9826790
its working, but there are still some problems, crash and logoff suddenly, black stripe on finder!
There is not much you can do, the web driver quality for Pascal card is that bad.

You may try completely remove all web drivers and 3x NVRAM reset, then re-install the V378 driver (please only do it if you know how to handle that "black screen", if your card's aren't flashed). There is a narrow chance that can fix some issues.
 

PHONO

macrumors newbie
Dec 11, 2018
1
0
Could you clarify a couple things for me, if possible? Our systems are spec'd very similarly. I'm currently running High Sierra with an RX580, and I am excited by the possibility of more upgrade options (as well as having a native boot screen again).

- The Bare Feats post you linked mentioned using dosdude1's Catalina patcher with good results. Is there any advantage to using OpenCore instead? Is OpenCore needed to get the boot screen?

- The Bare Feats post also mentions that the RX 5700 XT can be powered "using only factory PCIe bay power feeds" just like the RX580. If that is so, why are you using extra SATA-to-PCIe power cables?

- Is the "OWC version" of the RX 5700 XT special in any way? The same GPU with the same specs and product number is currently listed on Amazon for $100 less:


Thanks!



The Radeon RX 5700 XT was tested it last autumn: https://barefeats.com/cmp-5700-xt-vs-other-gpus.html

hint: This is an opened door for the Mac OS Big Sur.

REPORT: Sapphire Pulse Radeon RX 5700 XT 8GB GDDR6

This card is PC AND MAC compatible by default, no need to flash it.
I bought mine here: https://eshop.macsales.com/item/Sapphire/112930120G/

REQUIRE: Catalina 10.15.1 installed on your Mac Pro 5.1 only, with OpenCore or Clover.
*(use OpenCore by default, PART I, no need to follow Part II Advanced Configuration - at your own risks)

Performance: equivalent to the VEGA 64, BUT... no need to flash, and has boot screen

Power Consumption: dual 6 pins to 8 pins, plus dual sata 15pins to 6 pins. *see below for config

Outs: 1 x HDMI, 3 x DisplayPort 1.4

Compatibility: DirectX 12.0, OpenGL 4.6, Metal Supported, feature set macOS GPUFamily2 v1, macOS 10.15.1 Catalina or later required

Other: occupies 2 slots, with Boot Screen

ALERT: Don't go with the MacVidCards version "right now"... they are flashing it - don't know why, though... and their flashed version is not compatible with the latest OS, they announced it on their official site, to keep OSX 10.15.4 ... http://www.macvidcards.com/blog/dont-update-to-10155-with-efi-5700

I have the OWC version of Sapphire Pulse Radeon RX 5700 XT 8GB GDDR6, and even if it's a PCIe 4.0 card, it fits perfectly within the Mac Pro, power and data wise.

IF you have no need for the #3 and #4 Dock slots, use my trick instead of tweaking your Mac Pro with the PIXLAS mod...

Power consumption: 6 + 8 Pins: dual mini 6 pins to 8 pins, PLUS dual SATA to 6 pins. NO PIXLAS mod. This situation is for the MacPro 5.1, because the 7.1 has a different power manager.

- 18AWG Dual Mini 6 Pin to 8 Pin Male PCI-E Power Cord, 8$US at newegg.com
- Dual SATA 15Pin Male M to PCI-e 6 Pin Female F, 9$US at newegg.com, plug them in #3 and #4
- StarTech.com PCIEPOWEXT 8 in. 6 pin PCI Express Power Extension, 10$US at newegg.com to extend the Dual SATA, because it's not long enough..

Oh, btw, I bought that card because my RX 570*(no flash, no boot) was **** with the game RUST... now I see everything in 8k, imagine the beauty!


My System Report *(with 2 monitors, and NightShift works by default when set with kext in OpenCore):

Hardware Overview:

Model Name: Mac Pro
Model Identifier: MacPro5,1
Processor Name: 6-Core Intel Xeon
Processor Speed: 3.46 GHz
Number of Processors: 2
Total Number of Cores: 12
L2 Cache (per Core): 256 KB
L3 Cache (per Processor): 12 MB
Hyper-Threading Technology: Enabled
Memory: 48 GB
Boot ROM Version: 144.0.0.0.0
SMC Version (system): 1.39f11
SMC Version (processor tray): 1.39f11
Serial Number (system): C07L30L3F4MH


Radeon RX 5700 XT:

Chipset Model: Radeon RX 5700 XT
Type: GPU
Bus: PCIe
Slot: Slot-1
PCIe Lane Width: x16
VRAM (Total): 8 GB
Vendor: AMD (0x1002)
Device ID: 0x731f
Revision ID: 0x00c1
ROM Revision: 113-1E4112U-O45
Metal: Supported, feature set macOS GPUFamily2 v1
Displays:
24MP56:
Resolution: 1920 x 1080 (1080p FHD - Full High Definition)
UI Looks like: 1920 x 1080 @ 60 Hz
Framebuffer Depth: 30-Bit Color (ARGB2101010)
Display Serial Number:
Main Display: Yes
Mirror: Off
Online: Yes
Rotation: Supported
Automatically Adjust Brightness: No
24MP56:
Resolution: 1920 x 1080 (1080p FHD - Full High Definition)
UI Looks like: 1920 x 1080 @ 60 Hz
Framebuffer Depth: 30-Bit Color (ARGB2101010)
Display Serial Number:
Mirror: Off
Online: Yes
Rotation: Supported
Automatically Adjust Brightness: No
 

tuchubby

macrumors newbie
Jun 12, 2017
10
7
Gigabyte R9 280X Flashed works with boot screen. Windows 10 drivers (win&amd) do NOT work with flashed R9 280X. You will get a hard reboot or black screen once driver is loaded. You will have to go into safe mode and force driver to the default Microsoft Basic Display Adapter.
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Gigabyte R9 280X Flashed works with boot screen. Windows 10 drivers (win&amd) do NOT work with flashed R9 280X. You will get a hard reboot or black screen once driver is loaded. You will have to go into safe mode and force driver to the default Microsoft Basic Display Adapter.
UEFI Windows or legacy Windows?
 

unpapapro

macrumors newbie
Apr 30, 2020
22
7
Quebec City, Canada
Could you clarify a couple things for me, if possible? Our systems are spec'd very similarly. I'm currently running High Sierra with an RX580, and I am excited by the possibility of more upgrade options (as well as having a native boot screen again).

- The Bare Feats post you linked mentioned using dosdude1's Catalina patcher with good results. Is there any advantage to using OpenCore instead? Is OpenCore needed to get the boot screen?

- The Bare Feats post also mentions that the RX 5700 XT can be powered "using only factory PCIe bay power feeds" just like the RX580. If that is so, why are you using extra SATA-to-PCIe power cables?

- Is the "OWC version" of the RX 5700 XT special in any way? The same GPU with the same specs and product number is currently listed on Amazon for $100 less:


Thanks!

The Bare Feats text is based on the slim version of the card, which I did not test myself... some manufacturers have different specs. and I don't like patches... using OpenCore is not a patch, just some files added to the EFI...

for the price.. same thing... the OWC sell it at their own price... i'm not a Amazon fan...

So i install OpenCore, install Catalina, and plug the GPU...
 
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