You can get the bios directly from Dell:
http://downloads.dell.com/FOLDER03410618M/1/5470A12.exe
Using cmd extract the bios with:
5470A12.exe /writehdrfile
Copy the extracted files to a clean usb flash drive (fat32).
Open the laptop, disconnect batteries and hard disk. Also disconnect the power cable.
Connect the flash drive to the usb near the hdmi port and hold Win+B. Reconnect the power cable and wait around 15 seconds. Now click the power button and after a couple of seconds release the Win+B. You'll hear a few beeps and the power led flashing, the system will open the recovery and do the rest for you.
Guide for El Capitan:
http://www.tonymacx86.com/threads/guide-booting-the-os-x-installer-on-laptops-with-clover.148093/
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I read the whole topic and found a post from RehabMan that somehow got ignored. He gave the tip to use the correct ResetAddress and ResetValue on Clover.
Clover reference:
https://clover-wiki.zetam.org/Configuration/ACPI#ResetAddress-and-ResetValue
Checking FACP for the correct values:
Code:
[074h 0116 12] Reset Register : [Generic Address Structure]
[074h 0116 1] Space ID : 01 [SystemIO]
[075h 0117 1] Bit Width : 08
[076h 0118 1] Bit Offset : 00
[077h 0119 1] Encoded Access Width : 01 [Byte Access:8]
[078h 0120 8] Address : 00000000000000B2
[080h 0128 1] Value to cause reset : A8
[081h 0129 2] ARM Flags (decoded below) : 0000
PSCI Compliant : 0
Must use HVC for PSCI : 0
ResetRegister:
0xB2
ResetValue:
0xA8
Could someone test if this fixes the shutdown?