“Your Mac stores certain settings in a special memory area even if it is turned off. On Intel-based Macs, this is stored in memory known as NVRAM”
—-from Apple Support site: About NVRAM and PRAM
But on Hackintosh, there is no compatible NVRAM can be utilized by OS X. Thus, some functions will not work properly, such as:
1. Save current backlight-level for next boot/wakeup.
2. Keep “Find My Mac” working after system reboot.
3. For Clover & EFI users, NVRAM also contains boot-args which can be read and set during the booting stage.
To simulate NVRAM on Hackintosh, we can just do as following:
1. Save current NVRAM data to a file when system shutdown.
(If you use Clover as boot loader, then this step had already been done. No need to do this again.)
To achieve this, a shutdown script can help us:
a. Open Terminal, create and edit a file in /etc called rc.shutdown.local
$ sudo vim /etc/rc.shutdown.local
b. The script should be like this:
#!/bin/sh nvram -x -p >nvram.plist echo NVRAM Saved!
2. Set NVRAM form saved file right after system boot.
(This step is necessary even if you are using Clover)
Create a LaunchDaemons plist file:
a. Open Terminal, change to /Library/LaunchDaemons
$ cd /Library/LaunchDaemons
b. Create & edit a plist file, name it as you wish:
$ sudo vim com.delta.nvram.set.plist
c. Edit file like this:(Sorry for the bad format)
<?xml version=”1.0″ encoding=”UTF-8″?>
<!DOCTYPE plist PUBLIC “-//Apple//DTD PLIST 1.0//EN” “http://www.apple.com/DTDs/PropertyList-1.0.dtd”>
or download this file from HERE.
d. Fix file permissions:
$ sudo chown 0:0 com.delta.nvram.set.plist
Reboot, NVRAM simulation is done. Your backlight level, “Find My Mac” status should be saved and restored automatically.