XPS 8920 won't POST after clearing NVRAM in UEFI Shell - no video, no USB power, no recovery

Hi everyone,
I own a Dell XPS 8920 (motherboard 0DF42J, Intel H270 chipset) and after running the command dmpstore -d -all in the UEFI Shell to clear EFI variables, the system stopped booting completely.

Current behavior:

• System powers on, fans spin for a few seconds, then shut off.
• CPU and PCH get warm.
• No video output on any port (HDMI/DP).
• USB ports have no power (keyboard and flash drive LEDs stay off).
• No POST beeps, even with RAM removed.
• Tried full CMOS reset (battery out + RTCRST jumper).
• Tried Ctrl + Esc + BIOS_IMG.HDR / BIOS_IMG.RCV recovery on FAT32 USB — no response.
• PSU tested separately and is fine.

It looks like the BIOS firmware enters a pre-POST loop — possibly due to a corrupted NVRAM block or ME initialization failure.

I’d really appreciate advice on:

1. Any alternate method to trigger BIOS Recovery (jumper, specific USB port, key combo, etc.).
2. Availability of a complete .bin image of BIOS v1.1.15 for flashing with a CH341A + SOIC8 clip.
3. Confirmation from a Dell modder or engineer whether the 0DF42J board has a secondary recovery point or backup descriptor.

Thanks in advance for any insight or dump file that could help bring this board back to life.

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