How to Fix "Couldn't allocate runtime area" on Z790 motherboards

How to Fix "Couldn't allocate runtime area" on Z790 Motherboards

The error "Error allocating 0xXXXX Pages... Couldn't allocate runtime area" during boot indicates that OpenCore's memory management driver (OpenRuntime.efi) is failing to allocate a contiguous block of memory in the system's NVRAM/UEFI maps. This is very common on modern Z790 chipsets (like the Z790 Aorus Elite AX) when running macOS Ventura.

1. Configure Booter Quirks Correctly

Open your config.plist using ProperTree or OCAT and check your settings under Booter -> Quirks:

• AvoidRuntimeDefrag: Set to True (Crucial for UEFI runtime services).
• DevirtualiseMmio: Set to True (Shrinks MMIO space, creating room for memory maps).
• RebuildAppleMemoryMap: Set to True (or try False if combined with DevirtualiseMmio).
• SetupVirtualMap: Set to False (Z790 motherboard bios maps require this to be False, otherwise it panics).

2. Setup MMIO Whitelist

Some Z790 boards require specific memory regions to be whitelisted under Booter -> MmioWhitelist to boot Ventura successfully. You can generate a whitelist log using a debug version of OpenCore.

3. Update BIOS Firmware

Gigabyte and Aorus Z790 motherboards have received several BIOS updates fixing memory map layouts for compatibility. Download and flash the latest stable BIOS version from the official manufacturer support page, then restore your Hackintosh-specific settings (Disable Secure Boot, Fast Boot, CFG Lock, and enable VT-d, Above 4G Decoding).