Hello everyone,
I have a problem with my 20" iMac from early 2009. A few months ago, my father gave me the iMac to reinstall it and install a fresh operating system. At that time, the Mac had a 320GB Apple HDD and 8GB of RAM installed. Reinstalling proved difficult because the Mac does not show the boot selector. When I start with the Option key pressed, the screen just stays white, and the Mac does nothing. If I try to select a USB stick from the system via Startup Disk, it doesn't show up. However, in Disk Utility, my prepared USB stick is displayed as "bootable." In other forums, I had read that the HDD might be defective, so I replaced it with an SSD and reinstalled the OS (using a OSX 10.6 DVD and then updated to El Capitan). The problem persists.
To summarize:
Best regards,
T-Man_16
I have a problem with my 20" iMac from early 2009. A few months ago, my father gave me the iMac to reinstall it and install a fresh operating system. At that time, the Mac had a 320GB Apple HDD and 8GB of RAM installed. Reinstalling proved difficult because the Mac does not show the boot selector. When I start with the Option key pressed, the screen just stays white, and the Mac does nothing. If I try to select a USB stick from the system via Startup Disk, it doesn't show up. However, in Disk Utility, my prepared USB stick is displayed as "bootable." In other forums, I had read that the HDD might be defective, so I replaced it with an SSD and reinstalled the OS (using a OSX 10.6 DVD and then updated to El Capitan). The problem persists.
To summarize:
- Mac does not show the boot selector; screen stays white
- El Capitan is currently installed
- My goal is to update to Monterey using OCLP
- Various USB sticks
- Different keyboards
- Tested the USB stick on another Mac; it appears in the boot selector
- NVRAM reset
- SMC reset
- Changed CMOS battery
- Ran "csrutil-disable" command in recovery
- Tried booting directly from the stick using the "bless" command
- Downloaded iMac EFI Version 1.4 and tried to reinstall it, thinking it might be faulty (installer wouldn't open because I already have the "latest" installed, Boot Rom Version IM91.008D.B08)
Best regards,
T-Man_16
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