UPDATE: SOLVED! Turns out the issue that kept dosdude1's Catalina Patcher from creating a bootable USB volume was Apple's SIP. If you too encounter this problem and you're sure your downloads are not corrupted, reboot your machine into recovery mode (hold down "Cmd-R" on reboot), open the Terminal and disable SIP with the command "csrutil disable" (obviously, hit enter afterwards), then boot back into your current OS and create the bootable Catalina installer
Original post follows ------------------------------------
Hive mind,
I've run into a problem that's got me completely stuck - I installed Catalina on an old SATA SSD (Samsung 840 Pro) using dosdude1's fabulous patcher. The machine (*) will boot Catalina just fine using the original Radeon 5770 but as soon as I put the 580 (**) back in, the machine gets stuck with a black screen and the display complaining about "No signal".
I've tried all the usual... reset NVRAM ("Cmd-Opt-P-R" on boot), unplug everything but the 10.15 drive, etc. but I simply can't get the machine to boot with the 580 running Catalina.
Any pointers, tips, etc. I'd be most grateful for! ?
Thanks!
* – Mid-2010 cMP 5,1 single hex-core CPU @ 3.46GHz, latest firmware
** – This is the card I've got, it's been rock solid under Mojave. No boot screen, obviously but it works perfectly under any version of macOS 10.14: Sapphire 11265-01-20G Radeon Nitro+ Rx 580 8GB
Original post follows ------------------------------------
I've run into a problem that's got me completely stuck - I installed Catalina on an old SATA SSD (Samsung 840 Pro) using dosdude1's fabulous patcher. The machine (*) will boot Catalina just fine using the original Radeon 5770 but as soon as I put the 580 (**) back in, the machine gets stuck with a black screen and the display complaining about "No signal".
I've tried all the usual... reset NVRAM ("Cmd-Opt-P-R" on boot), unplug everything but the 10.15 drive, etc. but I simply can't get the machine to boot with the 580 running Catalina.
Any pointers, tips, etc. I'd be most grateful for! ?
Thanks!
* – Mid-2010 cMP 5,1 single hex-core CPU @ 3.46GHz, latest firmware
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