The 1151 DMG: What’s Inside the Pre-Built Hackintosh Image and Why It’s Risky

In early 2020, a pre-configured DMG image for LGA1151 motherboards started circulating in Hackintosh communities under the label “1151.dmg”. Unlike generic macOS installers, this image bundled a customized bootloader configuration, ACPI patches, and kexts for Intel 100/200/300-series chipsets. Its release filled a gap for users running macOS 10.13 (High Sierra) through 10.15 (Catalina) on hardware that Apple never officially supported — specifically the Skylake, Kaby Lake, and Coffee Lake generations. However, the convenience of a pre-built DMG comes with significant caveats regarding system stability, data integrity, and long-term maintainability.

What Is the 1151 DMG?

The 1151 DMG is not an official Apple disk image. It is a community-created archive that contains a pre-installed macOS environment (or an installer bundle) along with a complete EFI partition customized for LGA1151 motherboards. The typical contents include:

• OpenCore or Clover bootloader with a pre-configured config.plist
• ACPI tables (SSDTs) for fixing power management, USB, and sleep
• Kexts such as Lilu, WhateverGreen, AppleALC, IntelMausi, and USBInjectAll
• SMBIOS data (usually iMac18,3 or iMac19,1) for macOS compatibility
• macOS installer image (often High Sierra 10.13.6 or Mojave 10.14.6)

The image was originally compiled by a small group of maintainers who tested the configuration across a range of Gigabyte, ASUS, and ASRock boards. Its purpose was to provide a “drop-in” solution for users who already owned compatible hardware but lacked the time or expertise to build a custom EFI from scratch.

Supported Hardware

Compatibility is strictly limited to the LGA1151 socket. The DMG explicitly targets CPUs with HD Graphics 530, 630, or UHD 630 iGPUs and discrete GPUs from the AMD Polaris and Vega families. Nvidia Kepler cards (GTX 600/700 series) are also supported under High Sierra, but Pascal and Turing cards require web drivers that are not included. Below is a summary of tested hardware:

Motherboards with unsupported audio codecs or atypical USB controllers may require manual insertion of additional kexts or SSDTs beyond what the DMG provides.

Risks and Limitations

Using a pre-built DMG from an untrusted source carries risks. First, the image may contain outdated kexts or bootloader versions. The original 1151 DMG was built with OpenCore 0.5.7 and Lilu 1.4.3 — both are now several major versions behind.

Newer macOS releases (Mojave and Catalina) introduced stricter driver signing requirements and ACPI specification changes that the old kexts may not fully handle, leading to kernel panics or broken sleep/wake cycles.

Second, the SMBIOS included in the DMG is generic. Using an iMac18,3 SMBIOS on a Coffee Lake system, for example, can cause incorrect CPU power management and missing CPU topology. This results in higher idle temperatures and reduced performance. Users should always generate a proper SMBIOS matching their CPU generation using GenSMBIOS or a similar tool.

Third, the DMG’s ACPI tables are board-specific. The SSDTs for a Gigabyte Z370 Aorus Gaming 7 will likely cause boot failures on an ASUS Z370 Prime-A. The DMG maintainers tested only a handful of boards; deviations from the tested list require editing the config.plist and replacing SSDT files.

Finally, the DMG may have been modified after its initial release. There are reports of versions circulating with injected malware or backdoored kexts. Always verify the checksum against the original release post (MD5: a1b2c3d4e5f6... — though the exact hash changes per build). If no checksum is provided, do not use the image.

How to Verify and Use the 1151 DMG Safely

If you decide to use this DMG despite the risks, follow these steps to minimise data loss and ensure the image is not corrupted:

1. Verify integrity. Mount the DMG and run shasum -a 256 /Volumes/1151/1151.dmg. Compare the output to the hash published in the original thread. A mismatch means the image has been altered — discard it immediately.
2. Extract the EFI folder. Do not boot directly from the DMG. Instead, copy the EFI folder to a FAT32-formatted USB drive. This allows you to inspect and modify the configuration before any macOS installation.
3. Audit the config.plist. Open EFI/OC/config.plist (or EFI/CLOVER/config.plist) and check the PlatformInfo section. Replace the Generic SMBIOS with one generated for your specific CPU generation. For Coffee Lake, use iMac19,1; for Kaby Lake, use iMac18,1.
4. Replace kexts. Download the latest versions of Lilu, WhateverGreen, AppleALC, and IntelMausi from the respective GitHub releases. Replace the kexts in EFI/OC/Kexts (or EFI/CLOVER/kexts/Other).
5. Test with a spare drive. Install macOS on a secondary SSD or HDD. Do not write the DMG directly to your main system drive — the installer may attempt to reformat it without warning.
6. Disable SIP and SecureBootModel. In the config.plist, set csr-active-config to 00000000 and SecureBootModel to Disabled for initial installation. Re-enable after booting.

Even with these precautions, expect that not every feature will work out of the box. The DMG does not include patches for NVRAM emulation, so reboot cycles may fail to preserve volume selection. A custom nvram.plist is required for reliable booting.

Final Considerations

If you do decide to use the DMG as a starting point, at minimum update OpenCore to the latest stable release (currently 0.9.x) and replace every kext with the most recent version from GitHub. Then run GenSMBIOS to generate a SMBIOS that matches your exact CPU generation — don't rely on the generic iMac18,3. The real value of this DMG is in studying its config.plist and SSDTs to understand how ACPI fixes and kext loading order work together. That knowledge will help you build a proper EFI from scratch using the Dortania guide. A single mismatch in bootloader version or a missing SSDT can make the system unbootable, so treat the DMG as a learning tool, not a production-ready installer.