- Jan 11, 2019
- RX 580
- Classic Mac
I don't know if this will fix Your issue but try this:I'm hitting a wall wth Catalina upgrade. I have a Sapphire Nitro+ RX590 that worked just fine with 10.14 but can't figure out the black screen after 10.15.4 upgrade.
What I have tried so far:
None of that helped so far, the furthest I get is Apple logo with progress bar, then temporary artifacts in form of purple lines and then black screen, seems like the port has the power because the backlight is on and display doesn't go to sleep.
- Upgraded Clover to 5112, also tried Multibeast 12.1.0 Catalina Edition (that downgraded Clover to 5107)
- HDMI vs DP
- Disabled onboard GPU in BIOS
- Changed OS to Windows 8/10 and Windows 8/10 WHQL to disable CSM support
- WEG 1.3.8 and Lilu 1.4.3 to EFI/C/k/O, various combination of injecting/not injecting/blocking kexts in Clover boot.
- Clover boot in safe mode
- Added SSDT-EC.aml
What I have not tried:
I can boot with onboard Intel graphics (without acceleration but that's probably fixable), obviously that's not what I'm trying to get.
- Additional binary patches - I understand none are needed with Radeon cards
- Changing system definition from iMac14,2 - I have no idea what else to try and what effect would it have
- Flashing BIOS
- Messing with /L/E or S/L/E - looks like EFI/C/k/O is the preferred method with Catalina anyways
Please help me Obi Wan, you're my only hope
--> Connect Your monitor via HDMI
if this won't work, try changing your SMBIOS from iMac14,2 to Mac Pro 6,1.
NOTE: Remember that, in case this fix won't work, for some reasons You could be not able to boot so try this fix ONLY IF YOU CAN BOOT VIA USB (using the USB that You used for the install), eventually You can re-change the SMBIOS version and try something else...