Fedora 16 black screen with Radeon HD 6470M: partially solved?

[David G. Miller]

M. Fioretti <mfioretti <at> nexaima.net> writes:

> 
> On Thu, Dec 08, 2011 20:18:21 PM +0100, Marco Fioretti wrote:
> 
> > I've got a HP G6 1273SL laptop with this chipset and a live cd of
> > Fedora 16 x86_64, KDE spin... when I [boot] the screen goes
> > completely black.
> > 
> > if I... add to its initrd line the two parameters
> >
> > acpi_osi=Linux acpi_backlight=vendor
> > 
> > Fedora boots without problems, but the laptop is quite warm.
> 
> If I check the graphich chips status, I get:
> 
> #> cat  /sys/kernel/debug/vgaswitcheroo/switch
> 0:IGD:+:Pwr:0000:00:02.0
> 1:DIS: :Pwr: etc etc...
> 
> so, if I understand correctly, I MUST also disable the discrete
> graphic chip with a script like this:
> 
> #####################################################
> #! /bin/bash
> 
> modprobe radeon
> echo IGD > /sys/kernel/debug/vgaswitcheroo/switch
> echo OFF > /sys/kernel/debug/vgaswitcheroo/switch
> #####################################################
> 
> and then add to /etc/rc/rc.local
> Is this 
> 
Same problem with this video hardware:

00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core
Processor Family Integrated Graphics Controller (rev 09) (prog-if 00 [VGA
controller])
        Subsystem: Hewlett-Packard Company Device 1671
        Flags: bus master, fast devsel, latency 0, IRQ 41
        Memory at c0000000 (64-bit, non-prefetchable) [size=4M]
        Memory at b0000000 (64-bit, prefetchable) [size=256M]
        I/O ports at 4000 [size=64]
        Expansion ROM at <unassigned> [disabled]
        Capabilities: <access denied>
        Kernel driver in use: i915
        Kernel modules: i915

and responded to the same kernel parameter fix.  Thanks.  I encountered this on
a HP Pavilion gz-1279dx.

The next interesting question is this.  My Fedora installation is VERY portable.
 I have it installed on an external USB drive.  This way I keep my environment
with me whether I'm at work, working from home or working someplace else.  I
just plug in the external drive and boot the system to my FC16 installation. 
So, the question is, will adding the kernel parameters mess with my ability to
boot on systems that don't require them?

Cheers,
Dave