Re: Disable discrete GPU at boot?

[Marek Marczykowski-Górecki]

On Tue, Jan 13, 2015 at 01:16:15PM -0800, alexand...@gmail.com wrote:
> Hello!
>
> I have installed Qubes OS R2 on an HP ProBook 4530s.
> Due to HP's top engineering skills, the GPU overheated (long ago) so
> much,
> it literally cut itself out of the motherboard.
> This poses a huge problem, because the GPU is still detected and OSes
> still
> attempt to use it.
> Unfortunately, it doesn't work. It pretty much makes any OS or installer
> hang. That includes the "Test this media & install Qubes" option, it
> reports a crashed card and then it just hangs.
>
> Note: I did not install Qubes in basic graphics mode, hoping that it
> would
> use the integrated Intel HD GPU.
> Also, it hangs before I can put in the password to decrypt the HDD.
>
> Is there any way I can disable the discrete GPU? Like a GRUB option?
> Or do I have to install in basic graphics mode? And if I do this, can I
> use
> the integrated GPU later?

The right place for such questions is qubes-users ML, where I'm
redirecting the question right now.

--
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?

[Alexandru-Mihai Maftei]

The right place for such questions is qubes-users ML, where I'm
redirecting the question right now.

I apologize for posting in qubes-devel. I did not realize I had that group selected when I created the topic.

[cprise]

On 01/13/15 17:53, Marek Marczykowski-Górecki wrote:

On Tue, Jan 13, 2015 at 01:16:15PM -0800, alexand...@gmail.com wrote:

Hello!

I have installed Qubes OS R2 on an HP ProBook 4530s.
Due to HP's top engineering skills, the GPU overheated (long ago) so
much,
it literally cut itself out of the motherboard.
This poses a huge problem, because the GPU is still detected and OSes
still
attempt to use it.
Unfortunately, it doesn't work. It pretty much makes any OS or installer
hang. That includes the "Test this media & install Qubes" option, it
reports a crashed card and then it just hangs.

Note: I did not install Qubes in basic graphics mode, hoping that it
would
use the integrated Intel HD GPU.
Also, it hangs before I can put in the password to decrypt the HDD.

Is there any way I can disable the discrete GPU? Like a GRUB option?
Or do I have to install in basic graphics mode? And if I do this, can I
use
the integrated GPU later?

The right place for such questions is qubes-users ML, where I'm
redirecting the question right now.

I think your best hope is to disable the GPU in the BIOS settings.

[Alexandru-Mihai Maftei]

On Wednesday, January 14, 2015 at 5:13:54 AM UTC, cprise wrote:
> I think your best hope is to disable the GPU in the BIOS settings.

I can disable any device except the GPU.

I tried an installation in basic graphics mode, but that only seems to take me to a text-only installer, which doesn't even work.
There is an error in the console, but it does not fit on my screen - I only see the bottom of a stack trace.

[cprise]

Fedora forum is the better place to ask this question (more people who understand the bits you're dealing with).

If I were to make a guess as to a possible workaround, I'd try disabling Plymouth (graphical component of boot process) if possible. Also, you could try blacklisting nvidia drivers within the initramfs image (something like 'echo -e "blacklist nouveau\nblacklist nvidia" >> /etc/modprobe.d/nvidia.conf' once to create the conf file) or even disable the nvidia's pci device (something like 'echo "1-0:1.0" > /sys/bus/usb/drivers/hub/unbind' executed each time the system starts booting from initramfs ).

If those don't work, you may need to have the system repaired.



[Alexandru-Mihai Maftei]

I cannot even get to the part where I input my HDD decryption password.
Unless I am completely misunderstanding how the boot process works, all I can access is GRUB.

Also, repairing the laptop would cost me more than I'm willing to spend. A new motherboard alone, besides being extremely difficult to obtain, costs me £150 without shipping and won't even come with a discrete GPU.
Oh, and it's an AMD card.

[cprise]

On 01/15/15 15:25, Alexandru-Mihai Maftei wrote:

I cannot even get to the part where I input my HDD decryption password.
Unless I am completely misunderstanding how the boot process works, all I can access is GRUB.

Right. You would have to find some other way of editing the initramfs. Perhaps you could attach the drive to a working Linux system and go from there. Working around a deep hardware malfunction can get very involved...

Also, repairing the laptop would cost me more than I'm willing to spend. A new motherboard alone, besides being extremely difficult to obtain, costs me £150 without shipping and won't even come with a discrete GPU.
Oh, and it's an AMD card.

--

[Alexandru-Mihai Maftei]

 
That's an excellent idea. I'll see what I can do!

[Alexandru-Mihai Maftei]

I solved it, finally.

I've accidentally logged into my BIOS (actually a fucked up UEFI thing) as guest, and I saw an option to disable switchable graphics.
It turns out, that option does not disable the switching feature, it actually disables the discrete GPU.
I wonder why my BIOS administrator account couldn't do that, and how on Earth can a "guest" do that.
Obviously I need a password to log in as my admin account, and nothing to log in as guest...

I'm never buying laptops from HP again.
Horrible thermal management, retarded security.

At least now Qubes works perfectly!