How to Fix Installer Reboot Loops on Lenovo IdeaPad L340 Hackintoshes

How to Resolve Second-Stage Installation Stalls and APFS Write Failures

When installing macOS Tahoe on a Lenovo IdeaPad L340 Gaming laptop (Intel Core i5-9300H Coffee Lake), the system can boot successfully into the installer GUI, but reboot loop or stall after selecting the destination SSD. This behaviour is typically caused by Crucial SSD power management incompatibilities or selecting the incorrect bootloader option during the installation cycle.

1. Prerequisites

• Hardware Specs: Lenovo IdeaPad L340 Gaming, Intel Core i5-9300H, NVIDIA GTX 1650 (must be disabled), 16GB RAM, Crucial 1TB NVMe SSD.
• Required Kexts: Lilu, VirtualSMC, WhateverGreen, AppleALC, RealtekRTL8111, and NVMeFix (critical for Crucial SSDs).

2. Compatibility Snapshot

• Crucial SSDs: Crucial NVMe drives (such as P1, P2, or P3 series) have aggressive link-state power management that causes macOS APFS controller panics during disk writes.
• GTX 1650: The discrete Turing-based NVIDIA card is completely unsupported and must be deactivated.

3. Installation Preparation

1. Disable NVMe TRIM temporarily: To prevent write stalls during phase 2, configure OpenCore to bypass TRIM during the installation phase.

4. EFI and config.plist Review

1. Inject Boot Arguments: Ensure -wegnoegpu is added under NVRAM boot-args to disable the GTX 1650 dGPU.
2. Set TRIM Timeout: Open config.plist. Navigate to UEFI -> APFS. Set SetApfsTrimTimeout to 0 (this disables the TRIM operation on boot, preventing Crucial SSD write panics).
3. Kext Verification: Confirm that NVMeFix.kext is enabled in your Kernel kext list.

5. Post-Installation

1. Boot Picker Selection: After the installer copies files and reboots, do NOT boot from the USB installer again. In the OpenCore picker, you must select the option named macOS Installer. The system will reboot 2 to 3 times; always select the macOS Installer option until it is replaced by your target SSD name.

6. Troubleshooting

Reported Issue: Stuck in boot loops after drive selection

1. Unmapped USB Ports: If the installer loop continues, map your USB ports. Installer write cycles can fail if the target USB port drops offline when the kernel reloads.
2. Alternative SSD: If the Crucial drive continues to panic even with TRIM disabled, consider installing macOS on a compatible secondary SATA SSD or a Western Digital NVMe drive.

7. Dual Boot and Advanced Configuration

• Keep Windows and macOS on separate physical drives. The L340 has space for both an NVMe SSD and a 2.5-inch SATA HDD/SSD.

8. Verification, Maintenance and Rollback

• Verify Fix: Ensure the installation progress bar completes and boots to the macOS setup assistant.

9. References and Glossary

• NVMeFix: An open-source kext that improves compatibility and power management for non-Apple NVMe SSDs.