Arch Linux

zzano

Member

Registered: 2005-05-18

Posts: 40

LCD Monitor Problem

I just installed a new Sony SDM HS75P LCD monitor on my  Pentium 4. It works beautifully (1280 x 1024 @ 75hz.) on Windows and I decided to give it a try on Arch. Arch detected the monitor and appeared to set it up correctly. However, the display is shifted to the left by about 1/2  inch and I am not able to easily  access some of the left most icons as they are effectively "off the screen." According to the information displayed under Linux the monitor is also operating at 1280 x 1024 @ 75hz... just as in Windows. If I adjust the Horiz Centering control on the Monitor I can clear things up, but this is a bit tiresome as I have to shift between Linux and Windows for a few special applications. Is there any way I can make both systems display  my respective deskop consistently?
TNX.

T-Dawg

Forum Fellow

From: Charlotte, NC

Registered: 2005-01-29

Posts: 2,736

Re: LCD Monitor Problem

sounds like a video driver issue. Try changing that in your xorg.conf, maybe its using the wrong one or a generic..

lanrat

Member

From: Poland

Registered: 2003-10-28

Posts: 1,274

Re: LCD Monitor Problem

I had a similar issue with my new Fujitsu Siemens W19-1 LCD connected as external monitor to the notebook (i915). No matter what I used the LCD was not properly set. Then I found that using gtf (from xorg) I could produce a Modeline for xorg.conf that gave same result as yours. Correct resolution but the image shifted (only it was shifted to the right about 10cm). Pressing "auto" button on the LCD fixed things but only until next reboot. I experimented with different refresh rates in gtf and found that "overclocking" it a bit forced my LCD to auto fix the mode (just like by pressing "auto" button). This seems to work well so far. LCD info mode says I'm using 66 Hz but I used 70 Hz as a parameter for gtf (gtf 1440 900 70). I guess it's not that important. Everything seems stable and clear.

zzano

Member

Registered: 2005-05-18

Posts: 40

Re: LCD Monitor Problem

Very interesting. Is "gtf" a seperate application or is it a subdivision of the xorg.conf file?
TNX

mit3z_

Member

From: Latvia,Riga

Registered: 2005-06-06

Posts: 11

Re: LCD Monitor Problem

It`s a programm which comes with xorg to generate modelines.

vacant

Member

From: downstairs

Registered: 2004-11-05

Posts: 816

Re: LCD Monitor Problem

Gtf is good for creating modelines. You can also use xvidtune to correct the display bit by bit, and then xvidtune can write out the modeline you need.

Sometimes you may find modelines are ignored. If so (for fglrx module, may work with other drivers), try

Option "IgnoreEDID" "true"

in the device section of xorg.conf

lanrat

Member

From: Poland

Registered: 2003-10-28

Posts: 1,274

Re: LCD Monitor Problem

Isn't IgnoreEDID only for nvidia driver?

Anyway, running:

gtf 1280 1024 75

will produce:

 # 1280x1024 @ 75.00 Hz (GTF) hsync: 80.17 kHz; pclk: 138.54 MHz
  Modeline "1280x1024_75.00"  138.54  1280 1368 1504 1728  1024 1025 1028 1069  -HSync +Vsync

Place this in the Monitor section of /etc/xorg.conf. IIRC you'll only need to change "1280x1024_75.00" to "1280x1024" as it should correspond with Modes line in Screen section. Start X and read X log in /var/log - check for potential errors. If the LCD screen is still shifted try to experiment with highier values than 75 Hz.

vacant

Member

From: downstairs

Registered: 2004-11-05

Posts: 816

Re: LCD Monitor Problem

It works for ati binary driver too, e.g. search for EDID on this page

Run xvidtune from a shell, it lets you shift/stretch your display in real time rather than guessing. Once you've got the display shifted nicely, use the "show" option to write the modeline to the shell window.

kth5

Member

Registered: 2004-04-29

Posts: 657

Website

Re: LCD Monitor Problem

you should give xvidtune a try. it modifies timings on the fly and can produce a Modline that woks for you.

---

I recognize that while theory and practice are, in theory, the same, they are, in practice, different. -Mark Mitchell

zzano

Member

Registered: 2005-05-18

Posts: 40

Re: LCD Monitor Problem

Thanks to everyone who was kind enough to reply. I appreciate your efforts and will tinder with the various solutions over the weekend.

droog

Member

Registered: 2004-11-18

Posts: 877

Re: LCD Monitor Problem

I had the same problems, and more. I tried most of those options with my lcd, I ended up changing it from digital input to analog input and all the problems went away.

zzano

Member

Registered: 2005-05-18

Posts: 40

Re: LCD Monitor Problem

I am currently using analog input only .However, after reading the disclaimer for vidtune I was a bit nervous about blowing the LCD Monitor, as I just got it and it cost me a bundle. The current setting is 75hz and according to the manual the max is only 80hz... which doesn't leave much upside potential. I want to make sure that I don't end up with a pile of junk.

vacant

Member

From: downstairs

Registered: 2004-11-05

Posts: 816

Re: LCD Monitor Problem

That's why I'm recommending xvidtune rather than gtf.

With xvidtune, you can keep the frequencies, refresh rate and pixel clock the same and make minor adjustments.

If I get a distro setting my monitor to 59Hz when I know it can do 85Hz, then I'll use gtf to get me a modeline for 85Hz, with a way higher pixclock. I'll use that in xorg.conf and then when I get the card driving the monitor at 85Hz, I'll tweak with xvidtune.