Toshiba Satellite 2410-S203 Setup

[buckyball]

I believe that X is receiving bogus information from the EDID query on this machine's LCD display. It says the display width is 969 pixels, not 1024 (see attached snippet from XFree86 logfile).

This results in a vertical blank region on the right side of the screen when I set the display mode to "1024x768". I have tried a number of approaches to override this information in the XF86Config file with no success. I am unable to find any XF86Config settings that allow one to *explicitly* set the monitor's physical resolution.

Does anyone know where the EDID info for a laptop's internal LCD resides (system ROM BIOS, Video BIOS, etc.)? The response I got from Toshiba Tech Support was pretty useless.

Hardware:
Toshiba Satellite 2410-S203
Pentium 4-M / 1.8Ghz
768MB RAM
15" active matrix LCD (1024x768 max)
Nvidia GeForce4 420 Go / 16MB VRAM

OS:
Gentoo Linux 1.4rc1
XFree86 4.2.1
Nvidia driver 1.0.3123 (from sources)

Thanks in advance.

[aritger]

Yes, it's getting the wrong EDID.

Could you try loading the kernel module with NVreg_SoftEDIDs=0? If that doesn't help, try also setting NVreg_Mobile to either 2 or 4.

I hope that helps,
- Andy Ritger

[buckyball]

Yep, that did the trick!

Setting NVreg_SoftEDIDs=0 allows the driver to use the explicitly set values to be used. I'll post a followup "mini-HOWTO" on what worked so others may be saved the time.

Many thanks for the quick response!

BTW - Where does the EDID data actually "live" in the system?

[buckyball]

So here's what I learned on how to get X working at 1024x768 on this unit.

1) The unit returns a bogus EDID value for the screen width (969 pixels instead of 1024). This results in X having a vertical blank area on the right side of the screen when running at 1024x768. (I determined this by launching X with:
startx -- -logverbose 5
and then inspecting the X logfile (in /var/log/XFree86.0.log). The information of interest is located in the "EDID query" section of the log.

2) Overriding the settings in XF86Config is *not* sufficient, as the NVidia driver still tries to query the EDID info.

3) You need to load the NVdriver module with the "NVreg_SoftEDIDs=0" option. Once you verify that this works, add it to your "/etc/modules.conf" file so that this option always gets passed when the driver is loaded.

My XF86Config file is attached.

This is for XFree 4.2.1, NVidia driver 1.0.3123 (from sources) running on Gentoo Linux 1.4 with kernel 2.4.19 (vanilla-sources). YMMV.

Please post any questions you may have about the config to this thread so I can update or clarify.

Good luck!

[aritger]

Great! I'm glad that worked for you.

On laptops, the EDID is either generated ("SoftEDID" -- a software generated EDID), or selected from a table of hardcoded EDIDs, based on the Mobile kernel module option.

- Andy Ritger
NVIDIA Corporation

[saturnotaku]

Will using this method work for getting 1600x1200 resolution working on a laptop? I have a Dell Inspiron 8200 and intend to install Linux on it in the near future. Any resolution less than my native 1600x1200 looks like garbage so I want to make sure I can get this before I try to install anything. :)

[aritger]

The SoftEDID and Mobile kernel module options are very vendor specific. I believe for most (all?) Dell laptops with NVIDIA GPUs, SoftEDID=1 (the default) is correct.

[saturnotaku]

Good to know, thanks. :)

[slash14]

Yeah ! That's great : I've got a 1410-604 and had the same problem and now, it's fully working in 1024x768. THX for your help !

[Kaz2100]

I ran into same problem (EDID returns incorrect width) with Toshiba Satellite 1415S173.

Adding "IgnoreEDID" "on" option in XF86Config-4 *worked.*