Working with refit shell to enable GeForce 9400M G on MacBook Pro 5.1 running with Ubuntu

[Ga.One]

Right now I am having MacBook Pro. Well I am looking to work with refit shell so that I can enable GeForce 9400M G rather than that of NVIDIA GeForce 9600M GT. We know that refit shell is part of standard refit installation and you can simply load through by selecting terminal icon from refit menu at the time of first boot. Can you give me any idea how can I make the thing working for us?????

[Calvert]

You should use dmpstore to save the variable to the file or load the variable from the file so that you can use to change the values of these variables. You have to save the original value of gpu-power-prefs to the file and edit the copy of the file to set the new value.

dmpstore gpu-power-prefs -s fs0:\gpu-power-prefs.orig
cp fs0:\gpu-power-prefs.orig fs0:\gpu-power-prefs
hexedit fs0:\gpu-power-prefs

now you will need to change 01 00 00 00 to 00 00 00 00
you can check the same by running below mentioned command

comp fs0:\gpu-power-prefs.orig fs0:\gpu-power-prefs

now you will be able to set value of the gpu-power-prefs to the new value by using dmpstore

dmpstore gpu-power-prefs -l fs0:\gpu-power-prefs

By using new value you can exit shell and turn on and off the machine. You have to go back to the shell and perform dmpstore gpu-power-prefs. You will see new value of 00 00 00 00. If you run dmpstore legacyvgahandle then you will see handle should be changed that of the device e5.