Update README.md

Author: Ausdauersportler

README.md

@@ -14,7 +14,9 @@ iMac12,1 and iMac12,2 mid 2011
 
 Of course this tool can be used on any other Intel based system.
 
-The tool supports persistence, i.e. dumps from your BIOS or video BIOS can be saved on the USB device in the particualar workind directorey as described below.
+## Working directory with persistence
+
+The tool supports persistence, i.e. dumps from your BIOS or video BIOS can be saved on the USB device in the particualar working directorey as described below.
 
 After booting configure the local keyboard and check for the working directory using the `lsblk` command. 
 
@@ -34,7 +36,41 @@ To use the video flashing tools change working directory to:
 % cd /lib/live/mount/persistence/sda/flash/Video 
 `
 
-To use the BIOS flashing tools change working directory to:
+## AMD graphcis card flashing
+
+AMD card users can run the locally included amdvbflash software like this to save the existing vBIOS named OldBios.rom into the Backups folder
+
+`
+% ./amdvbflash -s 0 Backups/OldAMDBios.rom 
+`
+
+Flashing a new video BIOS stored in file NewAMDBIOS.rom from folder AMD
+
+`
+% ./amdvbflash -p 0 AMD/NewAMDBios.rom 
+`
+## NVIDIA graphcis card flashing
+
+Saving the original version to the Backups folder
+
+`
+./nvflash --save Backups/OldNVBios.rom
+`
+
+and
+
+```
+% ./nvflash --protectoff
+
+% ./nvflash -6 NewNVBIOS.rom
+
+% ./nvflash --verify
+```
+Reboot after flashing the video BIOS.
+
+## Using flashrom to save and write the iMac firmware (BIOS)
+
+To use the iMac/Mac BIOS flashing tools change working directory to:
 
 `
 % cd /lib/live/mount/persistence/sda/flash/Firmware