[SOLVED] Can't send output to external monitor

troncoso · 2009-12-01 15:07:25

I've got a Dell Inspiron 1501 laptop which I sometimes use to give presentations at my school. Last time, in mid october, it worked perfectly, but now my laptop and the digital projector seem to ignore each other. The only difference between last time and now is that I've updated the system.

This is output of xrandr -q:

$ xrandr -q
Screen 0: minimum 320 x 200, current 1280 x 800, maximum 4096 x 4096
VGA-0 disconnected (normal left inverted right x axis y axis)
LVDS connected 1280x800+0+0 (normal left inverted right x axis y axis) 331mm x 207mm
   1280x800       61.0*+

It says that VGA-0 is disconnected, which isn't the case. I've tried pressing Fn+CTR/LCD but it doesn't make any difference.

Can anyone tell me if I am missing something? What's wrong? Why doesn't it work now if it worked fine just over a month ago? Is this a problem with the new X server?

I know I'm asking a lot of questions, but I'd really appreaciate any help. I wouldn't like my students to get the idea that Linux is unreliable (or maybe that I'm just not smart enough).

Cheers

Last edited by troncoso (2009-12-18 19:47:58)

tavianator · 2009-12-01 16:52:59

Google seems to indicate that that laptop has an integrated ATI card. What driver are you running, and are you using KMS?

troncoso · 2009-12-01 17:04:31

Thanks for answering. Yes, it has an integrated ATI card, and I'm running the radeon driver without an xorg.conf. This is what "lspci -v" says about the card:

01:05.0 VGA compatible controller: ATI Technologies Inc RS482 [Radeon Xpress 200M] (prog-if 00 [VGA controller])
        Subsystem: Dell Device 01f5                                                                             
        Flags: bus master, 66MHz, medium devsel, latency 66, IRQ 17                                             
        Memory at c8000000 (32-bit, prefetchable) [size=128M]                                                   
        I/O ports at 9000 [size=256]                                                                            
        Memory at c0100000 (32-bit, non-prefetchable) [size=64K]                                                
        [virtual] Expansion ROM at c0120000 [disabled] [size=128K]                                              
        Capabilities: <access denied>                                                                           
        Kernel driver in use: radeon                                                                            
        Kernel modules: radeon, radeonfb

Cheers

tavianator · 2009-12-01 19:13:40

Does radeon mean the xf86-video-ati driver? This is the one I'd recommend, but it can't hurt to try alternatives. Also, are you using KMS?

troncoso · 2009-12-01 19:28:59

I'm not sure about KMS. The wiki says that since version 2.6.31, kms is available and is enabled by default in the default Arch kernel. Should I try to disable it? Would that help?
Cheers

troncoso · 2009-12-18 19:51:15

In the end I tried disabling KMS by adding "radeon.modeset=0" to the kernel in /boot/grub/menu.lst and it worked.

Arch Linux

#1 2009-12-01 15:07:25

[SOLVED] Can't send output to external monitor

#2 2009-12-01 16:52:59

Re: [SOLVED] Can't send output to external monitor

#3 2009-12-01 17:04:31

Re: [SOLVED] Can't send output to external monitor

#4 2009-12-01 19:13:40

Re: [SOLVED] Can't send output to external monitor

#5 2009-12-01 19:28:59

Re: [SOLVED] Can't send output to external monitor

#6 2009-12-18 19:51:15

Re: [SOLVED] Can't send output to external monitor

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