My notebook has two graphic cards and it suffers from severe overheating after installing Ubuntu (no problem with Windows 7 on the same machine).

I figured out that the problem may be in the graphic card and I would like to disable the discrete one.

I followed some tutorials on this topic (for example http://planetoss.com/articles/how-to-disable-the-discrete-amd-graphics-card-in-linux/).

But the problem is, that after executing the commands, nothing really happens and both GPU are still running.

Here is what I have done:

smajl@smajl-mini:~$ sudo chown smajl /sys/kernel/debug/vgaswitcheroo/switchsmajl@smajl-mini:~$ echo IGD > /sys/kernel/debug/vgaswitcheroo/switch
smajl@smajl-mini:~$ sudo cat /sys/kernel/debug/vgaswitcheroo/switch
0:IGD:+:DynPwr:0000:01:05.0
1:DIS-Audio: :Pwr:0000:02:00.1
2:DIS: :DynPwr:0000:02:00.0
smajl@smajl-mini:~$ echo OFF > /sys/kernel/debug/vgaswitcheroo/switch
smajl@smajl-mini:~$ sudo cat /sys/kernel/debug/vgaswitcheroo/switch
0:IGD:+:DynPwr:0000:01:05.0
1:DIS-Audio: :Pwr:0000:02:00.1
2:DIS: :DynPwr:0000:02:00.0

What am I missing here?

Also, more on the overheating topic: 1) Installed TLP 2) updated system 3) set power setting mode to "power save" ...and nothing helps

Tried same thing with Linux Mint without success. Is there anything else to try if I manage to disable the second GPU and the problem preserves? Otherwise I would have to get back to win in order not to melt my laptop.. :-/