Installation stuck on black screen

Hardware (ASUS prebuilt desktop):

  • ASUS ROG Strix G15DS (OEM prebuilt — limited BIOS)

  • AMD Ryzen 7 7700X

  • NVIDIA RTX 3070

  • M.2 NVMe (Windows on one SSD; empty second SSD as Linux target — dual-boot intent)

  • Monitor on DisplayPort (also tested HDMI)

Symptom:
GRUB menu loads fine. After selecting any entry, boot freezes at the EFI stub stage. Last lines on screen:

EFI stub: Loaded initrd from LINUX_EFI_INITRD_MEDIA_GUID device path
EFI stub: Measured initrd data into PCR 9

These lines show only on linux mint with compatibility enabled other distros get stuck before, right on choosing install.
Then a frozen screen — no kernel messages ever appear, keyboard goes unresponsive. Have to hard-power-off.

Already tried (no change):

  • All three GRUB entries: default CachyOS, LTS Kernel, Legacy Hardware (GPU nomodeset)

  • Kernel params: nomodeset, nouveau.modeset=0, iommu=off, acpi=off

  • Secure Boot disabled (OS Type → Other OS, cleared Secure Boot keys — confirmed off)

  • BIOS updated to latest (ASUS Windows updater)

  • fTPM disabled (TPM Device → Discrete TPM) — hang just moved from the PCR 9 line up to the “Loaded initrd” line, so TPM isn’t the root cause

  • Tested all video outputs: GPU DisplayPort, GPU HDMI, and motherboard iGPU HDMI — identical hang on all

  • Single monitor only

  • USB re-flashed in DD mode (Rufus); also tried ISO mode

  • Cross-checked other distros: Bazzite (NVIDIA) and Linux Mint Cinnamon hang at the exact same EFI stub line — so it’s not CachyOS-specific or a GPU/driver issue (fails before the kernel even starts)

Any way to solve this? I would love to use cachyOS

Intel RST off