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Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
Hello everyone! I need some help with my cMP 5.1
Bought a 2nd hand XFX Radeon VII, saw it working on the computer it was pulled off from.
Got home, replaced my RX 590 NITRO+ SE with the Radeon VII and got no boot screen on any output port on the GPU.
Plugged back my 590 and everything works as it should.
Tried running my machine without OpenCore, plugged my NVMe MacOS Catalina drive, unplugged the OC hdd and still no image on screen.
Plugged back the 590 without OpenCore and I had image on my screen.
Is there anything else left to try?

MP 5.1
CPU: 2x 3.46 Xeon
RAM: 20 GB
NVMe1: MAC OS CATALINA 10.15.7
NVMe2: WIN10 22H2
OC: 0.7.8 (Installed in HDD SLOT 4 EX FAT)
GPU: SAPPHIRE RX590 NITRO+ SE
 
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h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
Hello everyone! I need some help with my cMP 5.1
Bought a 2nd hand XFX Radeon VII, saw it working on the computer it was pulled off from.
Got home, replaced my RX 590 NITRO+ SE with the Radeon VII and got no boot screen on any output port on the GPU.
Plugged back my 590 and everything works as it should.
Tried running my machine without OpenCore, plugged my NVMe MacOS Catalina drive, unplugged the OC hdd and still no image on screen.
Plugged back the 590 without OpenCore and I had image on my screen.
Is there anything else left to try?

MP 5.1
CPU: 2x 3.46 Xeon
RAM: 20 GB
NVMe1: MAC OS CATALINA 10.15.7
NVMe2: WIN10 22H2
OC: 0.7.8 (Installed in HDD SLOT 4 EX FAT)
GPU: SAPPHIRE RX590 NITRO+ SE
For boot screen, Radeon VII need DirectGopRendering, which the RX590 may not, you better check if you enabled this option in the OpenCore config.

Since Catalina cannot be run on the cMP without patching. If you pull out the OC drive but you can still boot to that with your RX590. This is only possible because you patched Catalina.

For patched macOS, the GPU driver somehow may be "locked" to the GPU that ran the macOS installer. This can also explain why the GPU driver doesn't load for the Radeon VII, and you can't see anything.

In your case, I will say the first thing to try is just enable DirectGopRendering.
 

Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
Since Catalina cannot be run on the cMP without patching. If you pull out the OC drive but you can still boot to that with your RX590. This is only possible because you patched Catalina.

For patched macOS, the GPU driver somehow may be "locked" to the GPU that ran the macOS installer. This can also explain why the GPU driver doesn't load for the Radeon VII, and you can't see anything.

In your case, I will say the first thing to try is just enable DirectGopRendering.
Thank you for responding so fast!
Seems like I already had it enabled.
Still not getting image, could there be another setting preventing me from getting image?
What's the correct way of installing a Radeon VII GPU?
 
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h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
What's the correct way of installing a Radeon VII GPU?
Should be just plug and play (assuming both 8pin are connected).

Seems like I already had it enabled.
Still not getting image, could there be another setting preventing me from getting image?
May be you can try my pre-configured OpenCore package. I built that with my Radeon VII.

It should allow your card to display the boot screen like this
 
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Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
Im actually using your package since I first heard from OC few years ago, great stuff btw.
So I'm still not getting any image whatsoever.
Plugged the rx590 back, made a brand new Mojave install on an empty HDD and removed the OC HDD, and as expected I dont get a bootscreen but I can get to the log screen and work normaly from there.
Removed the rx590, plugged the Radeon VII and again no screen.
I was using your 0.7.8 package and updated to the most recent (0.8.8) but I'm still not having luck.
I started reading about Radeon VII's black screen issues, turns out there were certain versions that shipped without UEFI support, AMD later released a firmware update with UEFI support.
Could this be my problem?
I might have a chance to boot this from the pc it was plugged in and try to update the firmware and give it another shot.
So, could I be on to something here or am I just wasting time?
Thanks in advance Martin, really appreciate the help.
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
I started reading about Radeon VII's black screen issues, turns out there were certain versions that shipped without UEFI support, AMD later released a firmware update with UEFI support.
Could this be my problem?
I might have a chance to boot this from the pc it was plugged in and try to update the firmware and give it another shot.
So, could I be on to something here or am I just wasting time?
This is exactly what I want to suggest next.

You may try the attachment. I found it from my data drive, should be my own Radeon VII's ROM image backup.

Or download the ROMs from here, and test them one by one (even you should only need the 016.004.000.038.011717 ROM)
 

Attachments

  • Radeon VII.rom.zip
    184.2 KB · Views: 195
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Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
Great, I will try this out but I've never upgraded a GPU firmware, just wanted to ask:
Is this just like a regular installer or are there any instructions I need to look to update the firmware?
Sorry for the dumb question.
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
Great, I will try this out but I've never upgraded a GPU firmware, just wanted to ask:
Is this just like a regular installer or are there any instructions I need to look to update the firmware?
Sorry for the dumb question.
In Windows (native, not virtual machine), download ATIWinFlash, run it.

Then use it to dump your existing ROM image to backup.

And use it to load the new ROM image to flash your card.

I posted some info about how to mod the ROM and flash RX580 at here.

For your Radeon VII, you only need to dump and flash the card. Those process are discribed in the procedure section (you can skip the steps related to PolarisBiosEditor).
 
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Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
I went to see my friend, we tried all roms and I still dont have any image coming out from the gpu, I tried booting the system using my native mojave partition without OC or through OC trying to boot catalina or win10.
I verified that I was installing a different firmware every single time (the tool doesnt allow you to install the same one either way).
Right now the card has your ROM and it worked perfectly in my friends PC, every single rom worked with the card.
What else could I be missing?
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
Did you try another PCIe slot, or another Display Port output on the card?

And I assume you do power both 8pin on the Radeon VII, correct?
 

Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
Yes I've tried the 1st and 2nd PCIe slots and all outputs on the gpu.
GPU is powered by both 8pin connectors.
It works great on windows on PC, ran several benchmarks and works as expected.
 

Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
I'm currently using Martin's 0.8.8 package (started this thread with 0.7.8 and upgraded to latest version).

Here are my current partitions:
OpenCore 0.8.8 on HDD SATA slot 2
Mac OS Mojave 10.14.6 on HDD SATA slot 3
Mac OS Catalina 10.15.7 on NVMe through adapter PCIe slot 3
Windows 10 on NVMe through adapter on PCIe slot 4

XFX Radeon VII with vBIOS v105 (provided by Martin as well) on PCIe slot 1 (both 8pin power cables)

Right now the cMP wont output any image from any of the 4 outputs of the Radeon VII(3 DP 1 HDMI).
This same GPU boots and works just fine in a PC i helped my friend build.
It worked fine after I flashed every single vBIOS file, 3 from the TechPowerUp site, 1 from Martin's own Radeon VII and 1 more from the TechPowerUp site from an ASRock version which was the 1st with UEFI support which according to the flashing utility is the same as the one Martin provided, still I flashed every single one and tried it on my cMP with the same result every time.

Is it possible i have to plug my NVMe drive (a UEFI Win10 partition) into my friends PC, boot into BIOS and set it to UEFI (I think its also called legacy mode) so the card switches to UEFI mode after rebooting and logging back to Win10?
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
I'm currently using Martin's 0.8.8 package (started this thread with 0.7.8 and upgraded to latest version).

Here are my current partitions:
OpenCore 0.8.8 on HDD SATA slot 2
Mac OS Mojave 10.14.6 on HDD SATA slot 3
Mac OS Catalina 10.15.7 on NVMe through adapter PCIe slot 3
Windows 10 on NVMe through adapter on PCIe slot 4

XFX Radeon VII with vBIOS v105 (provided by Martin as well) on PCIe slot 1 (both 8pin power cables)

Right now the cMP wont output any image from any of the 4 outputs of the Radeon VII(3 DP 1 HDMI).
This same GPU boots and works just fine in a PC i helped my friend build.
It worked fine after I flashed every single vBIOS file, 3 from the TechPowerUp site, 1 from Martin's own Radeon VII and 1 more from the TechPowerUp site from an ASRock version which was the 1st with UEFI support which according to the flashing utility is the same as the one Martin provided, still I flashed every single one and tried it on my cMP with the same result every time.

Is it possible i have to plug my NVMe drive (a UEFI Win10 partition) into my friends PC, boot into BIOS and set it to UEFI (I think its also called legacy mode) so the card switches to UEFI mode after rebooting and logging back to Win10?
As long as you confirmed OpenCore is working (e.g. able to see the boot picker from another GPU. Or see the BoomROM version spoofed to 9144.0.8.8.0 (if you are using my package), then the Radeon VII should able to display even no OS installed. So, Windows 10 isn't required.

Of course, if you want to boot to that legacy Windows, you can't select that in the OpenCore boot picker. But it won't change the fact that OpenCore boot picker should able to show you the Mojave and Catalina options.
 

Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
Yeah I was just thinking that the GPU might be "locked" from running in the other mode all this time (forgot its name CSM maybe?), maybe I need to run the gpu natively in UEFI mode and that will switch it?
That's why I mention Win 10.

So the boot rom needs to be spoofed to 9144.0.8.8.0?
I haven't checked this, will do this ASAP.
 

Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
So I can confirm the boot rom is the same one you wrote.
OpenCore works great on my RX590, everything is working as it should.
It's just the Radeon VII, anything else to try?
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
TBH, I am really running out of ideas.

The card itself can work on a PC, which means all hardware are good, all ports are working.

You tried a few ROM image, including my dump which is known good. So, not VROM issue.

Same monitor, same cable for the RX590. So, not the cable / monitor. (But you may still check if the monitor side has Display Port version selector. If yes, try DP 1.2)

OpenCore is working, and I built that with my XFX Radeon VII. So, shouldn't be incorrect coding. (but we haven't check your original BootROM version, even that shouldn't make any difference)

Both 8pin powered, assuming the same 8pin cable is used, then not the 8pin cable.

Different PCIe slots tested, and the same slot works for RX590. So, not the PCIe slot.

OS version is irrelevant in this case. As long as there is a macOS, the OpenCore boot picker should able to show that.

Can you burn a Linux LiveCD for testing purpose?

You may first test the CD with the RX590, simply hold C to boot your cMP, and it should boot to the Linux LiveCD. If that works, then swap in the Radeon VII, and see if it can boot to the LiveCD as well.

Anyway, just to confirm, the Radeon VII is the only graphic card installed, correct?
 
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Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
I can try but I really don't know how to do it, should I just look it up like that?
How to burn a Linux Live CD?
 
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Bob Lodge

macrumors newbie
Original poster
Aug 22, 2021
26
1
Do I need a specific Ubuntu version?
The site offers many different versions (desktop, server, cloud, flavors, IoT) and I don't know which one to use.
Does it need to be a CD or can it be a USB stick?
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
Do I need a specific Ubuntu version?
The site offers many different versions (desktop, server, cloud, flavors, IoT) and I don't know which one to use.
Does it need to be a CD or can it be a USB stick?
Prefer CD / DVD. USB flash drive not alway scan boot on cMP, we better remove any unnecessary doubt.

Pretty much any version can do. In general, the newer the better. But all you need is just something should has Radeon VII support. As long as not too old. It should work.
 

tommy chen

macrumors 6502a
Oct 1, 2018
907
390
I would try to run the card with an external power supply, because one of my sapphire radeonVII,
also with downvolting, did not run at the backplane connectors.
therefore I also had to provide my test computer with the pixlas mod.
and since then the card runs without OC under mojave and with every OC version up to monterey.
 

AlexMaximus

macrumors 65816
Aug 15, 2006
1,232
576
A400M Base
When I installed my Pixlas mod, I noticed that the cable clamps that are tucked to the PSU cables are very tight. I had to squeeze some of the clamps with tweezers, otherwise the contact would have been not very good on some of them. In order to check on those clamps, you need to remove the yellow plastic housing of those clamps and inspect the metal contact and make sure it fully contacts into that cable. Once checked, you can then snap the yellow housing back on the metal contact. Just to be sure, I used my EVGA Powerlink as well with the power hungry GPU together with that pixlas mod. This way I never had a single problem so far. I just finished my final AMD 6800XT Alienware card mod. If every other options fails, you may want to check those cable clamps and consider using an EVGA Powerlink. Hope you will find the culprit.


IMG_3297.jpeg
 
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