Contribute
Register

Resolution Issue at POST, Clover Boot & Login Screen

Status
Not open for further replies.
Joined
Dec 4, 2011
Messages
175
Motherboard
Gigabyte Z390 Auros Pro
CPU
i7-9700K
Graphics
RX 580
Mac
  1. iMac
Mobile Phone
  1. iOS
Building a new rig and stealing my RX 580 for it and putting back my HD 6870 card in my current profile hack.
Using Clover pkg 5102
2 - Apple 20" Cinema Displays (only using one for now)

Downgrading OS to High Sierra from Mojave since old GFX card is not Metal capable.

High Sierra install working great with HD3000 DVI port.
BIOS set to Init Display First > Onboard ( Had it set to PCIx16 with RX 580, but with HD 6870, had to switch it to see POST with DVI onboard )

ISSUE >>

When I boot with DVI cable plugged into HD 6870, the resolution from POST to Clover boot screen is terrible, and login screen only shows 1/4 of the screen. System IS booted, but entire screen not visible. (see images)

Here's the weird part...

If I boot with monitor plugged into Onboard port, no issue... THEN unplug monitor from onboard and plug it right into the HD6870 and BOOM, all is well... Sleep and wake even work.

Here is another thread with the exact same issue, but he never solved it either:
Clover Boot: Screen resolution/partial display/scrambled

Can someone please help me solve this mystery so I can get on with installation in my new Hack?? Pretty please!? And THANK YOU

BTW: I'm using Lilu / Whatevergreen and the HD 6870 is correctly identified in About this Mac window (see image)
My third party kexts are installed in /Library/Extensions and NOT in Clover/Kexts/Other
Config Inject Kexts = Detect
No Graphics / GUI / Framebuffer editing in Config.

If you want me to post my Config, I will tomorrow, but I don't think it's the issue. ( I could most definitely be wrong )

Screen Shot 2021-06-14 at 11.56.51 PM.png
127543-3be34497e2afaa4650ac86596c286be1.jpg
IMG_2356.jpg
 
Building a new rig and stealing my RX 580 for it and putting back my HD 6870 card in my current profile hack.
Using Clover pkg 5102
2 - Apple 20" Cinema Displays (only using one for now)

Downgrading OS to High Sierra from Mojave since old GFX card is not Metal capable.

High Sierra install working great with HD3000 DVI port.
BIOS set to Init Display First > Onboard ( Had it set to PCIx16 with RX 580, but with HD 6870, had to switch it to see POST with DVI onboard )

ISSUE >>

When I boot with DVI cable plugged into HD 6870, the resolution from POST to Clover boot screen is terrible, and login screen only shows 1/4 of the screen. System IS booted, but entire screen not visible. (see images)

Here's the weird part...

If I boot with monitor plugged into Onboard port, no issue... THEN unplug monitor from onboard and plug it right into the HD6870 and BOOM, all is well... Sleep and wake even work.

Here is another thread with the exact same issue, but he never solved it either:
Clover Boot: Screen resolution/partial display/scrambled

Can someone please help me solve this mystery so I can get on with installation in my new Hack?? Pretty please!? And THANK YOU

BTW: I'm using Lilu / Whatevergreen and the HD 6870 is correctly identified in About this Mac window (see image)
My third party kexts are installed in /Library/Extensions and NOT in Clover/Kexts/Other
Config Inject Kexts = Detect
No Graphics / GUI / Framebuffer editing in Config.

If you want me to post my Config, I will tomorrow, but I don't think it's the issue. ( I could most definitely be wrong )

View attachment 521792View attachment 521793View attachment 521794

Hi there.

I'm no expert on your GPU BUT there is info in the Radeon Compatibility thread:


Looking for your GPU it shows:

AMD.jpg


Not sure if this is a problem with your FrameBuffer but it hints at some relevancy.

:)
 
Hi there.

I'm no expert on your GPU BUT there is info in the Radeon Compatibility thread:


Looking for your GPU it shows:

View attachment 521796

Not sure if this is a problem with your FrameBuffer but it hints at some relevancy.

:)
Hello!
thank you for the reply...

ive read through this thread a few times, and there is great info there; however, the most interesting part of my issue is the “hot swap” I can do from booting with the onboard graphics and having correct resolution... then taking the monitor cable out of the onboard and plugging it into the GFX DVI works.

so the GFX is being correctly ID”d and I have full resolution At some point seemingly after I login.

I know the second DVI port is non functional, but if I want a second monitor, I have a DVI to mini DP adapter that works great. I’m just staying with one monitor, cuz I’m gonna use the second one for my new rig.
 
Hello!
thank you for the reply...

ive read through this thread a few times, and there is great info there; however, the most interesting part of my issue is the “hot swap” I can do from booting with the onboard graphics and having correct resolution... then taking the monitor cable out of the onboard and plugging it into the GFX DVI works.

so the GFX is being correctly ID”d and I have full resolution At some point seemingly after I login.

I know the second DVI port is non functional, but if I want a second monitor, I have a DVI to mini DP adapter that works great. I’m just staying with one monitor, cuz I’m gonna use the second one for my new rig.

Okay, understood. :thumbup:

Have you tried with the Lilu/Whatevergreen pair installed in the EFI rather than L/E ?

This problem is usually called the GPU re-initialisation that happens when boot graphics switch over to OS control. Search for "Black Screen at Boot" and you will find it affects AMD as well as Nvidia. Whatevergreen should fix this if installed.

Config Inject Kexts can only work for kexts in the EFI folder.
 
Okay, understood. :thumbup:

Have you tried with the Lilu/Whatevergreen pair installed in the EFI rather than L/E ?

This problem is usually called the GPU re-initialisation that happens when boot graphics switch over to OS control. Search for "Black Screen at Boot" and you will find it affects AMD as well as Nvidia. Whatevergreen should fix this if installed.

Config Inject Kexts can only work for kexts in the EFI folder.

This seems like the root of the issue.... When graphics switch to OS control...

Can you help me understand something?
What is the order of operations from hitting the power button on your computer?
I know that POST is first
Then right after POsT the Bootloader “loads” Right?
That being true, when are the kexts that reside on EFI in Other folder injected?
Are they injected before the bootloader boot screen Is displayed? Thereby setting GFX before loading the OS?

If the above is true, I will try adding Lilu / Whatevergreen to the EFI folder To see if that helps.

Now if I do that, can I keep Lilu / Whatevergreen in L/E?
I currently have config for Kent injection set to “detect.”
My assumption here is that the Kexts in EFI will load first, and the rest of the kexts in L/E will load during OS boot.
 
This seems like the root of the issue.... When graphics switch to OS control...

Can you help me understand something?
What is the order of operations from hitting the power button on your computer?
I know that POST is first
Then right after POsT the Bootloader “loads” Right?
That being true, when are the kexts that reside on EFI in Other folder injected?
Are they injected before the bootloader boot screen Is displayed? Thereby setting GFX before loading the OS?

If the above is true, I will try adding Lilu / Whatevergreen to the EFI folder To see if that helps.

Now if I do that, can I keep Lilu / Whatevergreen in L/E?
I currently have config for Kent injection set to “detect.”
My assumption here is that the Kexts in EFI will load first, and the rest of the kexts in L/E will load during OS boot.

The Bootloader is the first thing loaded after you have selected a boot drive from BIOS. Usually we don't have to do this because we only have one.

The Bootloader menu appears and there we get some choices on what to do. For example with Clover you can really choose which kexts and SSDTs to load, or not, before they get injected by the bootloader. OpenCore is more like a real Mac in this regard but still flexible.

Once the Bootloader has injected the Patches, the Kexts and the Renames we want, then the OS is kicked into life.

Kexts in EFI are not loaded in the conventional sense that macOS loads and caches them. They are all injected "under the radar". Kexts in L/E are cached. You can actually see either type once the desktop arrives, if they have executable code in them, by using Terminal and the command "kextstat".

:)
 
ok well I know that in bios I had PCIex16 as initial display... if I do that, the resolution output during post is low And continues to be low at clover boot screen as you can see by the pics I posted in post #1.

Then when I select the OS to boot, I get black screen until login screen and that’s when I see the other image I posted in post #1. That’s when apparently the OS takes over graphics and only shows me the small portion of the login screen as if the rest of the screen data is not being sent to display...

Like it’s taking the low res size of the screen from booting and when it goes to full resolution its Simply scaling the visible resolution during boot and not displaying the rest.

Does that make sense?
 
Did a couple more tests...

1. if I set bios to init first display=onboard
2. Have DVI to Apple Cinema Display plugged into the onboard port
3. post looks correct & clover boot screen correct resolution.
4. get normal boot screen with apple logo and progress bar
5. Login screen is correct and I log in
6. while logged in, take DVI cable out of onboard port & plug it into the HD 6870 and it works just fine. Acceleration, dual screen with second apple cinema using DVI to mini DP adapter

then I do the opposite...

1. Set bios to init PCIex16 first VGA is set to always enable on both tests
2. Have DVI cable plugged into GfX
3. i see post, low res clover boot & and select boot drive
4. Black screen until login & I get the small corner of login screen in post #1
5. Take DVI cable out of GFX and plug into onboard port, no display at all
6. Plug it back into GFX, no display at all.

this happened when I upgraded from Lion to El Cap a long while ago with same GFX and the issue just seemed to fix itself.

i had bios set to init PCIeX16 first... the only thing is that with El Cap I never saw the boot screen with apple logo... screen would go black until login screen.

This was also before I was using Lilu and Whatevergreen.

there has to be a solution.... something is happening with card initialization i think during POSt because the text during post with GFX looks slightly larger and clover boot screen has crappy res as seen in photo post #1. So I’m not even sure booting verbose would help, but I can try it.

so could this possibly be an nvram issue??
Anyone that has a solution would be greatly appreciated.
 
Found this guide... Lot's of things to do in this guide and not even sure if this fix would apply to my HD6870.
So not sure I wanna go through all this... Unless someone else has tried it and can confirm success with AMD6xxxController's.

Guide How to Patch AMD Framebuffers for High Sierra using Clover

It's surprising to me no one else has experienced my same issue....

@discreetlogic - You and I have / had virtually the same hardware. Care to weigh in on this thread?
 
@rocco_77 Lots of technical info here, only thing I can add for now is :

- check the dvi cable, at least try another cable, or go hdmi (which is nice to have audio if that's relevant to the setup)
- if the video card has dual bios, try the other setting. (My 580 can do opencore at higher resolutions using the normal bios, but the higher performance bios setting gives a lower res at the bootloader.)
 
Status
Not open for further replies.
Back
Top