dark screen in current [SOLVED]

[lipk]

Hi,

I've just switched to current, and I'd prefer it to 13.0, but I have a big problem:

Since I firstly suspended the machine, the screen got dark; even reboot didn't help (BIOS splash's also dark!!). I had had this problem with almost all distros I've tried so far (the only exception is SUSE, which could not suspend at all ), and there ACPI was the guilty doubtlessly (how strange....). The solution was to play a bit with the "Screen brightness" slide in the power manager application, but I couldn't find any option like that in the Xfce power-manager.

Help please, this dark screen makes me depressed

[thenktor]

Notebook or desktop TFT?

Try the command line tool xbacklight.

[lipk]

notebook.

xbacklight does nothing... xbacklight -get or -steps n says "no outputs have backlight property", -dec or -inc don't have any noticeable result.

But I caught an error message during boot:

Code: Select all

ACPI I/O resource (number) [address] confilcts ACPI region SMBI [address]

[gapan]

xfce4-power-manager includes a brightness panel plugin. Did you try to add that to your panel and use it?

[lipk]

Yes, it works. Thanks a lot!!! Is there any way to control it from the command line?

[gapan]

Not really sure, but try to find a brightness file in your /proc/acpi/video/...
and try to echo a value to it:

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echo -n 50 > /proc/acpi/video/VGA/LCD/brightness

for example.

[lipk]

It works. Thanks, gapan!

[klanger]

I have similar problem, but with my eeepc running live-cd (with remembered settings).

Every time eeepc suspends, it can't wake up - the little hdd-led indicates disk writes (even though system is on usb-stick) but nothing happends, just black screen (no way to jump out of X) & no keyboard working - only power-off button works OK.

I've 2GB RAM & and live-cd is on 2GB USB-stick could that be a problem (when I had 1 GB RAM once or twice it has suspended corectly).

edit:
problem is solved - it is the RAM problem - with 1GB of RAM eeepc suspends&resumes correctly
probally my usb-stick is too small (only 2GB) for 2GB RAM...

[Shador]

problem is solved - it is the RAM problem - with 1GB of RAM eeepc suspends&resumes correctly
probally my usb-stick is too small (only 2GB) for 2GB RAM...

To my knowledge it only depends on swap space. The live cd usually tries to enable all swap partitions available. When hibernating the ?biggest? one is chosen for hibernate. Generally it's recommended for hibernate to have a swap partition 130% the size of the available RAM. Though anything from 100% on could work.
I used to think hibernate would just abort if there isn't sufficient memory, but it seems to be kind of unpredictable. I just tried and it aborted but also restarted X.
Anyway this can be quite nasty. If memory is full and swap is used additionally (i.e. not anymore enough space for hibernate) it already occurred to me that I hibernated my laptop and directly put it into my bag. Some time later I take it out again realizing by the warmness of the case that it had been up a while before running out of battery.
Also some applications like VirtualBox can have very weird results.

[klanger]

Thanks Shador.

I don't have swap on usb-stick (salix-live) & I don't use hibernate (it doesn't work probably due to no swap). Suspend with 1GB of RAM and 2GB usb-stick works like a dream though

It is not the most needed feature in an OS for me, but since it worked earlier it is nice that it works now.