is this fix safe

[Dans564]

hey guys,
trying out fedora for the first time I think. Fedora 16 looks awesome and ubuntu and mint where getting old. So I replaced Mint 11 with fedora 16. My laptop, hp dv6t, has switchable graphics. I don't game on linux so i would prefer to have the radeon disabled at boot.

On Mint 11 adding this to the rc.local disabled it at boot and just used the intel chip:

modprobe radeon
echo OFF > /sys/kernel/debug/vgaswitcheroo/switch


My question is, is this an ok fix for Fedora 16?? I hope someone knows!

Thanks in advanced!


---------- Post added at 08:18 PM ---------- Previous post was at 07:25 PM ----------

update:
I tried the above solution and rebooted but the discrete card is still running (I can hear the fan).
So how do prevent this card from running in fedora???

[friTTe]

Try googling for Vga Switcheroo..had some links and stuff but my laptop has given up on me =D

---------- Post added at 02:35 AM ---------- Previous post was at 02:34 AM ----------

sorry i couldnt be more helpful

[Dans564]

yea i have read quite a bit about that, although im not too concerned about being able to switch. I only want to use the intel chip. No worries though! hope you get ur laptop up and running again! Thanks for the help =D

---------- Post added at 09:02 PM ---------- Previous post was at 08:54 PM ----------

this card has zapped my battery lol. 100% to 31% in about an 1hour and 30minutes. Usually that takes closer to 6 housrs...

---------- Post added 10th November 2011 at 12:11 AM ---------- Previous post was 9th November 2011 at 09:02 PM ----------

i usually dont bump this soon, but i need this laptop to work when I go to school tomorrow.
again, the question is, how do I fully disable the amd card so that it does not use any battery?
Realllly sorry for bumping but this is urgent!

[AdamW]

it's usually safer to do something like this from the BIOS; doesn't the laptop's BIOS offer an option to disable the AMD chip?

anyway, there shouldn't be anything dangerous about using that command on Fedora, no.

[Dans564]

no the bios doesnt offer such an option. the above doesnt seem to work

[stevea]

My Lenovo BIOS has a switch to select the graphics hardware (Integrated vs Discrete) and also separately to enable/disable NVidia Optimus. Sadly a lot of laptops lack this sort of BIOS control.

If I enable Optimus I get ....

[root@crucibulum Desktop]# cat  /sys/kernel/debug/vgaswitcheroo/switch
0:DIS: :Pwr:0000:01:00.0
1:IGD:+:Pwr:0000:00:02.0

Where the "IGD:+:" means that the Integrate Graphics Device is the current controller.
Sending the OFF command turns off the non-controlling device, so If I do

[root@crucibulum Desktop]# echo OFF >  /sys/kernel/debug/vgaswitcheroo/switch
[root@crucibulum Desktop]# cat  /sys/kernel/debug/vgaswitcheroo/switch
0:DIS: :Off:0000:01:00.0
1:IGD:+:Pwr:0000:00:02.0

which powers off the Discrete Nvidia controller. But the OFF command powers off whichever device is not controlling.

So it's probably best to select the integrated graphics and then power off the 'other' like
echo IGD > /sys/kernel/debug/vgaswitcheroo/switch
echo OFF > /sys/kernel/debug/vgaswitcheroo/switch
and that needs to be executed before the X-session starts (or else restart an Xsession w/ ctrl+alt+bksp).



FWIW the curent driver commands thru the debugfs 'switch' pseudo file are:
OFF - power of the unused vid
ON - power on the nuused vid.
DIGD - delayed switch to intergrated graphcs (on the next xsession start)
DDIS - delayed switch to discrete Nvidia on next Xsession
IDG - immediate switch to integrated vid
DIS - immediate switch to discrete vid
MIGD - mux switch to integrated vid
MDIS - mux switch to discrete vid

The Mux switch options are new - and I haven't played with them.

[Dans564]

how can i get:

echo OFF > /sys/kernel/debug/vgaswitcheroo/switch

to happen automatically??

[AdamW]

rc.local is the right place, but you should make sure it starts with the line #!/bin/bash and is executable.

[Dans564]

check and check... for now im just manually switching the card off after boot, but this is far less then ideal.