Legacy BIOS caveats

The Lenovo G570 comes with a legacy BIOS, i.e., it does not adhere to the UEFI standards. Thus, it is not possible to also boot off of GPT disks. However, due to the way OpenCore handles the boot drive, it is necessary to format the drive to GPT and load OS X. OpenDuetPkg will be used to emulate an UEFI environment in order to boot into the OS. Thus, do not try to format the drive in MBR.

Firmware

Lenovo did a good job with writing the BIOS firmware. There exists MAT support and all Slide values are accessible. FW NVRAM exists, but cannot be accessed for some reason. Refer

Speaking of things that are absent, this firmware implements a Whitelist for WiFi cards. If you can find a decent Mini-PCIe WiFi card that can work with both OS X and this laptop, don't forget to flash the modded BIOS to get rid of the Whitelist and also access advanced BIOS settings.

Advanced BIOS edits

TBA

UI / UX

• Boot chime enabled 🎵
• The boot picker displays itself in an old-fashioned 1024x768 resolution. If an attempt is made to fix it using the ForceResolution parameter in OpenCore, it derps out (and prevents the laptop from booting)
• The in-built PS/2 Keyboard does not work in OpenCore boot menu. Internal trackpad and external keyboard/mouse work fine. Also, when any key is pressed using the inbuilt keyboard, the touchpad freezes.
• Resolution and inbuilt keyboard works properly if OpenCore is booted from EDK DUET older than 2020. (See cheatsheet below)