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efi

  1. F

    Help flashing EFI bios chip with CH341A

    I need some help using a CH341A programmer and SOP8 clip on my late 2013 15" MBP. End goal is to read and save the ROM, and modify the Big Sur firmware so that I can undervolt again (get rid of "OC_Locked" in VoltageShift). Someone has detailed this at the GitHub page here. I installed Xcode...
  2. Alvin777

    How Do I "Inject" or Install Grub 2 as the Bootloader (Preferably w/ a 3rd-Party GUI) of my Windows 11 USB Flashdrive Installer & Boot EFI Based Macs?

    Hi GNU Linux bootloader friends. I need to have a Windows 11 or 10 USB Installer in a Flashdrive to be on the ready to fix any Windows installation on any computer (Mac or PC) and any EFI (old Macs use EFI) or UEFI (relatively new PCs and new Macs use UEFI). I burn the Windows .iso using Rufus...
  3. Alvin777

    Has Anyone Successfully Booted a Windows 10 or 11 USB Installer on EFI Macs?

    Hi, if anyone has successfully booted the Windows 10 or 11 USB installer on EFI Macs (I wish it was UEFI, this would have been solved months ago) how did you do it? Did you inject it with a bootloader from Linux? I have to reinstall the Windows (Boot Camp), preferably just an overwrite of...
  4. S

    Other Mac Pro 5.1 Windows Legacy boot from NVME

    I'll be brief. I want to understand why in the iMac 27 2013 you can install Windows in legacy mode, windows 7 and windows 10, and both systems perfectly see nvme disks and make it possible to install the system and boot from the nvme itself. While Mac Pro 4.1 5.1, when installing the system in...
  5. Alvin777

    Boot Camp's EFI Partition Keeps Mounting

    Hello Mac friends. When Boot Camp was booting, after a highly recommended app WinRE (it's the best after trying many apps and technical command line things for many grueling days to almost two weeks coz' to reinstall and redownload wasn't an option) made it bootable again (it did convert the GPT...
  6. Alvin777

    What's the Syntax to Use DISM to Repair Another Drive w/ Windows On It?

    Hi, I messed up the EFI of my Boot Camp Windows 11 by renaming the Microsoft folder in there coz' of experimentation (it's on my 2nd internal hard disk on the Mac, actual Mac, not Hackintosh) but I do have a Windows to Go that I can boot to. I've repaired the bootloader EFI I believe but it...
  7. Alvin777

    Boot Camp Won't Appear on Apple's "Boot Manager" w/ Option Held Upon Reboot

    Hello I recently uninstalled something in the EFI (in this EFI folder I erased folders named EFI, System and boot.efi in the secondary macOS volume (my setup, in one drive is a quadruple boot at that time, which included Boot Camp. I had the EFI mounted with an app). I deleted that volume, that...
  8. K

    running Windows with fully disabled dGPU on an old MBP

    Hi everyone. I'll describe my setup and what I have already tried first. I have installed Big Sur on MacBookPro6,2 (15'' mid-2010) via OCLP. Then I decided to install Windows 10 in (U)EFI mode. Officially my mbp supports only 8.1 via non-UEFI (legacy) mode. Currently Windows works fine, both...
  9. MacinMan

    Need help installing Ubuntu to an external drive for my iMac 27" from late 2015

    Hey all, I am stuck on getting a Ubuntu 22.04 to put the bootloader on the external drive and NOT the drive with the macOS boot loader. I am able to successfully install linux to an external drive, and it runs. However, even though I tell the installer to put the boot loader on the external...
  10. dimakot08

    iMac 2011 + HD5750 new EFI

    Hello everyone. Sorry for the translator. I have an iMac 2011 27" i7 and I needed to replace the video card in it. I purchased an HD 5750, it worked without any problems, but then the firmware update came and now the screen is black when turned on, but the iMac loads and works 100%. I understand...
  11. tinygoblin

    macOS Big Sur 11.6.3 or 11.6.4 install.log of T2-equipped Intel Mac?

    Hello, I'm trying to figure out how to update EFI firmware (BootROM, iBridge) of my T2 Intel Mac without updating macOS. This cannot be done using regular Terminal methods (efiupdater and eficheck Terminal tools do not support T2-equipped Intel Macs). According to this article firmware on all...
  12. tinygoblin

    Updating T2-equipped Intel MacBook Pro EFI Firmware (BootROM)

    Hello, Is there some way to update EFI firmware (BootROM & iBridge) without updating macOS Big Sur or macOS Monterey on an Intel Mac with T2 chip? Mac is capable of running macOS Catalina. I have already tried installing FirmwareUpdate.pkg using a well-known method by Pepijn Bruienne. That PKG...
  13. KayvK

    Looking to flash older firmware onto an iMac 5k Late 2015 (17,1)

    I've extracted the firmware files from the Sierra installer. An older guide (https://forums.macrumors.com/threads/guide-how-to-get-back-old-efi-after-downgrade-from-yosemite.1803934/) said to flash the .scap files using the bless command. The only problem? Any iMac newer than 15,1 only has a .fd...
  14. D

    Running Windows through Bootcamp on a MacBook Pro 2011 17" with disabled dGPU?

    Hi everyone, First post! I have a Macbook Pro 2011 17" with a permanently disabled AMD dGPU (modified EFI through Linux and also removed resistor R8911 to cut voltage to the dGPU). Currently running Sierra as an easy option to retain the control of brightness with the least effort. I know my...
  15. A

    Corrupted EFI partition map or APFS container?

    My Macbook Pro (2012, latest Mojave) started having some hickups not long ago where the screen would freeze for a minute or two and then go back to normal. Then one time it just got really slow and froze up every 10 seconds so I tried to shut it down but it would only shut down to a black screen...
  16. M

    MP 1,1-5,1 Mac 1,1 With no operating system

    Hello! I recently bought an old Mac Pro 1,1 I managed to get it working with a Windows copy. However when messing around with the hard drive portions I somehow made it worse. Long story short I got a clean hard drive with no operating system and have no idea how to get in to “bios”/ Efi to...
  17. N

    Request: A1466 EMC2925 Bios

    Hi there! I'm having trouble with this 13" MacBook Air. The computer turns on, fan spins, all power rails OK, but no chime, no backlight, etc. So, I removed the U6100 and soldered one from a non-identical non-donor board, and it works "OK"*, so... The firmware is corrupt. Does anyone have a...
  18. nigification

    MP 1,1-5,1 Mac EFI Roms for GPU's .. Am I missing something?

    Hey guys, this is my first post here. So I'm currently running a Mac Pro 4,1-5,1 on High Sierra with a GTX 960 4G card. All is well, although obviously, the lack of boot screen support blows. I've been reading this forum, along with a few of those personal websites that a few have published...
  19. T

    Is there an eficheck tool for Arm Macs?

    Earlier Macs had the possibility to check the EFI firmware or even create a complete dump of it from within the OS: https://www.macrumors.com/2017/09/25/macos-high-sierra-weekly-efi-security-check/ https://eclecticlight.co/2018/06/02/how-high-sierra-checks-your-efi-firmware/ This was...
  20. MartinNobel

    Hidden EFI Menu on the original iMac4,1 firmware

    Hey everyone, Around a month ago I got my hands on a 2006 iMac5,1 with an Intel Core 2 Duo with the intention of attempting to access the hidden generic EFI menu on the original iMac4,1 firmware documented on this forum...