Black Screen for 20-30 Seconds on Boot with RX 480

[nineniner]

Is there a fix for the "black screen for 20-30 seconds on boot" issue with AMD cards? I have an rx 480 and it works without any kexts or boot flags, but it alwasy has a black screen for about 20 seconds when I boot in, which makes having an ssd pointless for boot times. This is NOT the "black screen" issue that exists on mac pro 6,1, imac 17,2 etc where the screen stays black forever until you apply a fix. This issue is NOT fixed with agdp aptch, lilu, etc, and it DOES work after 20 seconds after boot.

 

[UtterDisbelief]

Is there a fix for the "black screen for 20-30 seconds on boot" issue with AMD cards? I have an rx 480 and it works without any kexts or boot flags, but it alwasy has a black screen for about 20 seconds when I boot in, which makes having an ssd pointless for boot times. This is NOT the "black screen" issue that exists on mac pro 6,1, imac 17,2 etc where the screen stays black forever until you apply a fix. This issue is NOT fixed with agdp aptch, lilu, etc, and it DOES work after 20 seconds after boot.

Well as no-one else has come on-board, something occurred to me reading your problem. (And because you sound as though you are pretty much up to speed PC and Hackintosh wise, this might seem trivial...)

When something like this happens it's a good idea to boot into verbose mode.

What seems to be happening is that the boot process is waiting on some hardware to reply or initialise, causing the pause. When it times-out the boot continues.

I don't think it's particularly AMD related, although it might be in your case. Plenty of AMD cards run without showing this tendency etc.

Your profile shows a 1060 Nivida card. Is the other hardware in your build the same and you've just changed the GPU? If so, remove the Nvidia drivers and any references/kexts related to them. Don't inject Nvidia etc.

Hopefully the verbose output will show you where the pause is occurring.

 

[nineniner]

Well as no-one else has come on-board, something occurred to me reading your problem. (And because you sound as though you are pretty much up to speed PC and Hackintosh wise, this might seem trivial...)

When something like this happens it's a good idea to boot into verbose mode.

What seems to be happening is that the boot process is waiting on some hardware to reply or initialise, causing the pause. When it times-out the boot continues.

I don't think it's particularly AMD related, although it might be in your case. Plenty of AMD cards run without showing this tendency etc.

Your profile shows a 1060 Nivida card. Is the other hardware in your build the same and you've just changed the GPU? If so, remove the Nvidia drivers and any references/kexts related to them. Don't inject Nvidia etc.

Hopefully the verbose output will show you where the pause is occurring.

Thanks for the reply. Unfortunately, it doesn’t seem to be a pause or hanging issue. The computer boots in fine, it’s just a black screen for the first 20 seconds or so. I know it boots in because I could hear a YouTube video begin to play right away (if I restart and tell it to reopen my windows in restart), so I know it’s just a video issue and not the booting actually pausing. I replaced the nvidia with this 480, and did a clean install so it can’t be anything nvidia related.

 

[UtterDisbelief]

Thanks for the reply. Unfortunately, it doesn’t seem to be a pause or hanging issue. The computer boots in fine, it’s just a black screen for the first 20 seconds or so. I know it boots in because I could hear a YouTube video begin to play right away (if I restart and tell it to reopen my windows in restart), so I know it’s just a video issue and not the booting actually pausing. I replaced the nvidia with this 480, and did a clean install so it can’t be anything nvidia related.

Okay, understood

Going further out on a limb then ... Maybe you have iGPU set as primary graphics in the BIOS? I'm not familiar with the specific available settings for your motherboard, but it sounds as though the video is outputting somewhere before macOS realises it's the wrong port and switches (?) The only other likely places are iGPU or another GPU port such as HDMI, Display or DVI. You may have covered this already, but try iGPU "Auto" or even "Disabled" with PCI-e as Initialsed First, etc. If you have other cables available to your monitor, check those?

Could all be way out, but worth checking. There has to be a reason for this unusual behaviour etc.

 

[macSteve83]

Thanks for the reply. Unfortunately, it doesn’t seem to be a pause or hanging issue. The computer boots in fine, it’s just a black screen for the first 20 seconds or so. I know it boots in because I could hear a YouTube video begin to play right away (if I restart and tell it to reopen my windows in restart), so I know it’s just a video issue and not the booting actually pausing. I replaced the nvidia with this 480, and did a clean install so it can’t be anything nvidia related.

I have a w7000 in one of my builds, it should work without any kext but when all of my 3 monitor was connected at boot it goes black, for me solved the issue inject ati, load vbios e deinit on config.plit with clover configurator

 

[nineniner]

Okay, understood

Going further out on a limb then ... Maybe you have iGPU set as primary graphics in the BIOS? I'm not familiar with the specific available settings for your motherboard, but it sounds as though the video is outputting somewhere before macOS realises it's the wrong port and switches (?) The only other likely places are iGPU or another GPU port such as HDMI, Display or DVI. You may have covered this already, but try iGPU "Auto" or even "Disabled" with PCI-e as Initialsed First, etc. If you have other cables available to your monitor, check those?

Could all be way out, but worth checking. There has to be a reason for this unusual behaviour etc.

Set PCIE to primary instead of auto, and even disabled igpu, and same issue. Let me try different ports.

Good NEWS! I have narrowed down the issue to something about my ports. I am using one of the HDMI ports and the DVI port on the card, where the issue happens. I tried using just one monitor (I unplugged the DVI port), and the same issue persisted. Then I tried just using the DVI port, and the issue went away! So it has something to do with using the HDMI port, whether by itself or in dual, it doesnt matter. I will try other port arrangements and see if that fixes it.

 

[nineniner]

I have a w7000 in one of my builds, it should work without any kext but when all of my 3 monitor was connected at boot it goes black, for me solved the issue inject ati, load vbios e deinit on config.plit with clover configurator

I tried deinit, vbios, and ati inject, and same problem. Good NEWS! I have narrowed down the issue to something about my ports. I am using one of the HDMI ports and the DVI port on the card, where the issue happens. I tried using just one monitor (I unplugged the DVI port), and the same issue persisted. Then I tried just using the DVI port, and the issue went away! So it has something to do with using the HDMI port, whether by itself or in dual, it doesnt matter. I will try other port arrangements and see if that fixes it.

 

[nineniner]

Ok great news, I tried using both HDMI ports instead of dvi+hdmi, and it seems to have solved it. Now its only a few seconds late because during clover boot, and MacOS boot, the second screen turns off, and doesnt reactivate until it boots in, which takes about 5 seconds to power on after it detects a signal again. Is there a way in clover to tell it to keep both screens on throughout the boot process?

 

[UtterDisbelief]

Ok great news, I tried using both HDMI ports instead of dvi+hdmi, and it seems to have solved it. Now its only a few seconds late because during clover boot, and MacOS boot, the second screen turns off, and doesnt reactivate until it boots in, which takes about 5 seconds to power on after it detects a signal again. Is there a way in clover to tell it to keep both screens on throughout the boot process?

Good news

Hopefully someone with a similar dual-monitor setup can offer a remedy for the lesser delay