How EFI works and how to spot a tech charlatan

[Rominator]

I've been selling EFI cards for more than 10 years.

I recently had an amazing moment where I read  "low-level programming in EFI C. Nobody will be happy if we rush and your MBP becomes an unbootable brick."

This is baloney.

EFI is a file on peripherals that tells the OS how to use the device.

Only way to turn something into an "unbootable brick" is to write to the bootrom. From 12 years of selling EFI cards this has never been a problem. If you have a USB stick with some EFI code that gets read at boot, BIG DEAL. It won't write to the machine's boot rom.

There is a HD partition with EFI on it, but this is not nearly as important as the EFI in the EEPROM chip soldered onto the logic board. All the peripherals that have EFI are the same as a USB stick, remove them and their EFI doesn't matter.

Darthvader guy and DOSDUDE are offering EFI NVME updates that write to the EEPROM chip on logic board. This could "brick" your machine. They warn you about what this means. But a simple eGPU hack that uses EFI from a file elsewhere poses no risk WHATSOEVER.

Someone who tells you otherwise is a liar and tech charlatan. Don't wander out into the desert following a mindless fool.

EFI from an external source (like GPU or USB stick) is  like a story you read in the newspaper at your breakfast table. You can choose to be moved by it, or set it down and walk away. It has no lasting power unless a specialized program writes it into the system boot rom. Completely harmless, like a butterfly landing on your finger, it has no lasting effect WHATSOEVER.

Don't believe me? Ask the above mentioned folks who know what they are talking about. A USB stick with eGPU EFI is as harmless as junk email you get for mail-order brides or African Prince scams. Only affects you if you buy into  the gibberish.

There is a reason why our EFI eGPU  cards  were called "breakthrough" BEFORE any wannabes posted about EFI. See Barefeats.com for the truth. Or keep reading nonsense in the echo chamber,  your individual choice.

[DarthnVader]

What was that about Dave?

Anyone thinking of altering and flashing their logic boards boot rom should use extreme care, all the normal warnings apply, it could brick your Mac, burn your house down, kick your dog, or knock up your teenaged daughter.

Anyway, two completely different targets, obviously  if you are dealing with an add on PCI card that has a ROM chip on it, it's best to just flash that rom chip with a Mac compatible firmware if the device needs to take part in the boot process. However what users have been doing is adding NVME booting to their Boot ROM, because we have no source of M.2 boards with a ROM chip, and I'm not aware any even exists.

There is the hope of the "Holy Grail" of getting cards with GOP roms working with cMPs, but it's just idle talk, no one is really actively working on it, and other than a few reports no one really knows how to do it, or if it will even work.