Radeon RX 580 Sapphire 8GB Black Screen.

[sotongster]

make sure csm is disabled. i used to have this issue. not anymore after i disabled it in bios

 

[rootlexa]

Hi all! I have similar problem with my Sapphire Pulse RX 580. HDMI works fine, but gives only 30Hz in 4K resolution, so it's not acceptable. DP signal disappears after initial apple logo. If I connect both HDMI and DP (to the same monitor) MacOS seems to see it and shows it in system information, but still no signal if I switch to it. Also for some reason system information shows 3 monitors. Interestingly enough, when I tried PiP (Picture in Picture) feature of my monitor to see both signals on the screen simultaneously, I see DP desktop, but if I switch to a regular mode - no signal again. Also for some reason integrated graphics doesn't appear in system information nor DPCIManager. I tried everything from this thread (or other places that I found) and nothing seems to help. I have installed Mojave 1.4.2. I've tried following:
1. Installed latest WhateverGreen + Lilu
2. Applied patches for com.apple.driver.AppleGraphicsDevicePolicy
3. Tried to manually specify in clover framebuffer+InjectATI+RadeonDeinit
4. Various stuff to make integrated graphics appear (but that's not a priority)
I have CSM disabled in BIOS. Please help! I'm attaching some screenshots, EFI and IOReg.

 

[rootlexa]

anyone can help?

 

[rootlexa]

I managed to enable integrated GPU by injecting Intel and selecting proper ig-platform-id. Still no luck with DP :/

 

[sbeaber4]

Is your cable dp 1.2 or higher?

 

[rootlexa]

yes, I tried 3 difference cables, 1.2, 1.4

 

[CaseySJ]

yes, I tried 3 difference cables, 1.2, 1.4

If your goal is to drive the 4K monitor at 60Hz (not necessarily through DP), but you’re getting only 30Hz from HDMI, are you using an HDMI 2.0 cable?

 

[rootlexa]

I don't think so.. Well, I guess that's an option, but I would also like to fix this configuration problem, may be it has some other consequences.

 

[CaseySJ]

I don't think so.. Well, I guess that's an option, but I would also like to fix this configuration problem, may be it has some other consequences.

This is a long shot but i’ll mention it anyway...

When I first installed the Radeon RX 580, the motherboard BIOS was unable to display any video through any of the ports on the card. Mojave was okay with HDMI and I didn’t try DP. Baffled by this, I contacted Gigabyte Tech Support, but they couldn’t find anything on their end after attempting to reproduce the problem.

It then occurred to me that I had used this card in a crypto mining rig where I had flashed it with a low-power, high memory clock BIOS. After restoring the original BIOS, the problem disappeared.

 

[rootlexa]

Not my case unfortunately I installed it straight from the box.