No video in 11.10b2 on HP dv7-6165us

Did you check the MD5 sums (https://help.ubuntu.com/community/HowToMD5SUM) of the downloaded .iso images and also verify the burned CD's with the "Check disc for defects" menu item? (To access this on the desktop CD, you must press Spacebar when you see the person and keyboard icons at the bottom center of the screen, during boot.)

I'd not run md5sums so here goes. Well, since the Linux on this dv7-6165us box is useless I'm reduced to running Win7-cygwin based iso tests.

Both kubuntu-11.10-beta2 iso files have good md5sums.

The kubuntu-11.10-beta2-alternate-amd64.iso CD ran the integrity check with no errors and told me so.

The kubuntu-11.10-beta2-amd64.iso CD gave a a black screen when I tried to run the integrity check. I could hear the CD grinding away but saw nada. N.G.

Now to find another machine here with a functioning Fedora 15 and do md5sums against the two media.

OK. Both CDs gave the correct md5sums:

md5sum run on CD of kubuntu-11.10-beta2-desktop-amd64.iso:

[lars@lars-laptop ~]$ dd if=/dev/cdrom bs=2048 count=355478 | md5sum
7466556a448bdcc9c2f091ceca3f1678 -
355478+0 records in
355478+0 records out
728018944 bytes (728 MB) copied, 274.828 s, 2.6 MB/s

md5sum run against CD of kubuntu-11.10-beta2-alternate-amd64.iso:

[lars@lars-desktop Documents]$ dd if=/dev/cdrom1 bs=2048 count=355990 | md5sum
355990+0 records in
355990+0 records out
729067520 bytes (729 MB) copied, 146.396 s, 5.0 MB/s
b5143f4a7933f69fc8449da0446f5978 -

I'm trying to run kubuntu on this dv7-6165us because Fedora 15 hung during "discovering hardware..." Less than useful.

Now, kubuntu 11.04 booted and ran just fine but does not support HP's Ralink 5390 wireless chip. Kernel 3.0 contains the support, so ... I tried kubunto 11.10.

What video chip do you use?

It is an AMD Radeon HD 6620G integrated into the silicon of the a8-3500m APU. There is also a graphics card, a AMD Radeon HD 6755G2 with its own 1GB GDDR5 memory. With the Catalyst drivers the two GPUs run together under Crossfire, but normally the 2nd GPU is unused.

Try the boot option:

nomodeset

You could also maybe remove one of the video devices, get installed, the put the card back in. Could help

I tried nomodset. It suppressed that bright horizontal bar that was appearing before the screen went black, but other than that there was no change. Still a black screen. I noticed 3 warnings as I booted. The only one I could read (curse you, fast quad-core!) said the ACPI package was empty.

Reading the HP docs more carefully I now see that the AMD Radeon HD 6755G2 discrete graphics is a chip on the mobo, not a card. No practical way to remove it. I guess I am SOL until the kernel catches up to this AMD processor & graphics.

Note that kubuntu 10.04 does not have a black screen. Its graphics works correctly. Now if I can just figure out how to add the driver for the Ralink HT5390 wifi adaptor to kubuntu 11.04 I'll have an acceptable Linux running on this laptop while the kernel marches on.

Thanks for your help. Y'all have been most responsive.

So far I understood Radeon HD 6xxx series is still not supported.
I hav the same problem with a Radeon HD 6470M.
Ubuntu 10.04 (64 bit version) works, but the screen is set to 1024x768

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

I wonder if this is a backlight problem (see bug 765438).

There are several workarounds for bug 765438, which are presented in various places in the bug (in the description and comments). For your convenience, they are:

(1) https://bugs.launchpad.net/ubuntu/+source/linux/+bug/765438/comments/2

(2) If that doesn't work, you can try the workaround described in the bug's description, i.e., after booting, run this command (in a Terminal window or virtual console) to manually set your backlight to the highest brightness:

sudo setpci -s 00:02.0 F4.B=00

(If that works, you can set up your computer to run that automatically as part of the start-up process.)

(3) If that doesn't work either, you can try using a patched kernel and power manager, as described at https://bugs.launchpad.net/ubuntu/+source/linux/+bug/765438/comments/11.

(4) If that fails, and you're on a 2.6.38-series kernel, you can downgrade to the 2.6.35-series, which does not seem to have this problem (or does not have it as often).

If you have trouble understanding or implementing any of these workarounds, please feel free to post a reply in this question, and I'll provide further assistance as best I can.

Eliah,

My problem is that the screen starts out black and stays that way. Ubuntu
11.10 desktop amd64. Earlier I tried installing a Kubuntu 11.10 beta as
well as Fedora 16 alpha and got a black screen there too. No way to know
what I'm doing; no visual feedback. Seems to be a kernel 3.0 issue. I'll
try running 11.10 desktop minus X-windows, see if I can update grub there
(less feedback needed in a full-screen terminal :-).

  --Lars

On Sat, Oct 15, 2011 at 9:50 AM, Eliah Kagan <
<email address hidden>> wrote:

> Your question #172376 on xserver-xorg-video-ati in Ubuntu changed:
>
> https://answers.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+question/172376
>
> Eliah Kagan posted a new comment:
> I wonder if this is a backlight problem (see bug 765438).
>
> There are several workarounds for bug 765438, which are presented in
> various places in the bug (in the description and comments). For your
> convenience, they are:
>
> (1)
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/765438/comments/2
>
> (2) If that doesn't work, you can try the workaround described in the
> bug's description, i.e., after booting, run this command (in a Terminal
> window or virtual console) to manually set your backlight to the highest
> brightness:
>
> sudo setpci -s 00:02.0 F4.B=00
>
> (If that works, you can set up your computer to run that automatically
> as part of the start-up process.)
>
> (3) If that doesn't work either, you can try using a patched kernel and
> power manager, as described at
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/765438/comments/11.
>
> (4) If that fails, and you're on a 2.6.38-series kernel, you can
> downgrade to the 2.6.35-series, which does not seem to have this problem
> (or does not have it as often).
>
> If you have trouble understanding or implementing any of these
> workarounds, please feel free to post a reply in this question, and I'll
> provide further assistance as best I can.
>
> --
> You received this question notification because you asked the question.
>

Are you able to see text on your screen when you switch to a virtual console with a terminal running on it? (Ctrl+Alt+F1)

Eliah,

My apologies for the delay in replying but in the process of trying to run
this test I succeeded in completely trashing my new laptop. I'm now
reformatting the disk and reinstalling Win7 and Kubuntu 11.04. Getting to
where I could try ctrl+alt+F1 when the screen was black completely defeated
me. I'd upgraded my 11.04 kubuntu to 11.10 so I should have been able to
boot, wait a long time, enter my password blind, press Enter, wait awhile,
and press cntl+alt+F1 but grub clobbered the MBR before I got a chance.

I did determine that adding "nomodeset" to the 11.10 Desktop CD boot kept
the video alive but I could never get X-windows started (startx, etc). Lack
of knowledge I expect. :-(

  --Lars

On Sun, Oct 16, 2011 at 11:15 PM, Eliah Kagan <
<email address hidden>> wrote:

> Your question #172376 on xserver-xorg-video-ati in Ubuntu changed:
>
> https://answers.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+question/172376
>
> Status: Open => Needs information
>

>
> Eliah Kagan requested more information:
> Are you able to see text on your screen when you switch to a virtual
> console with a terminal running on it? (Ctrl+Alt+F1)
>
> --
> To answer this request for more information, you can either reply to
> this email or enter your reply at the following page:
>
> https://answers.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+question/172376
>
> You received this question notification because you asked the question.
>

Eliah,

Again, my apologies for the delay. Lots of futzing around with kubuntu 11.01 DVD and Desktop and Fedora 16 beta without much luck. Until now.

I reinstalled kubuntu 11.04 and told Software Updates to take me to 11.10. After it finished I tried adding "nomodeset" to the boot command and still got a black screen. Then I remembered your ctrl+alt+f1 trick, and, voila!, I got a login prompt! I logged in and found I had wired network access (Fedora 16 did not) and the wireless light was lit saying that the Ralink chip driver was alive. Real progress!

I found the blog entry http://linux-software-news-tutorials.blogspot.com/2011/10/ubuntu-1110-oneiric-problems-with-ati.html and followed their very clear instructions for installing the latest Catalyst driver. All went well, so I rebooted. Black screen again. Fooey!

For the heck of it I powered off, rebooted, and edited "nomodeset" into the boot command. IT WORKED! I had a working window manager and all was good! So I've edited "nomodeset" into /boot/grub/grub.cfg.

Why did this work? I thought "nomodeset" disabled the automatic kernel-level mode detection that allowed a window manager to run. What am I missing? I am happy, but I'm confused.

I'm glad you were able to get it working!

Since Ctrl+Alt+F1 was successful, this is not a backlight problem, so it's not bug 765438 after all. (I just want to make sure that's stated somewhere in this thread, since it's quite justifiably linked to that bug because of related troubleshooting, but I don't want people with that bug to come here and wonder if your solution should fix the bug...which they shouldn't.)

nomodeset prevents the kernel from giving video mode data to the video at boot time. Sometimes the data provided by the kernel are wrong, and result in a failure to display anything (either because the video card does not support the values given, or because it does but the screen doesn't support the output that results, for example because it might be too high resolution given the color depth and refresh rate...though I think more subtle incompatibilities are also possible). When you run with nomodeset, the X server sets these data itself, which sometimes works out better.

From power on to a graphical session goes, roughly speaking:

BIOS --> boot loader (grub-pc, i.e., GRUB2) --> kernel --> init (upstart) --> display manager --> X server --> window manager

So generally, the video mode is already set up when the window manager runs, with or without nomodeset.

I'm tireder than I thought. Corrections:

"I don't want people with that bug to come here and wonder if your solution should fix the bug...which IT shouldn't."

"nomodeset prevents the kernel from giving video mode data to the video CARD at boot time."