New flat panel monitor doesn't work with RH9

[andysdp]

I am very new to Linux. I have installed Red Hat 9 on an old 500mhz machine with no problems and was enjoying getting to grips with Linux ! I was running the Linux machine along side my main XP machine, sharing keyboard, mouse and CRT Monitor through a KVM (Belkin) - All working great.

Just treated myself to a new flat panel screen (LG L1710S), which is nice, however it goes into powersave mode on the linux machine. Red Hat starts the usual boot sequence - the text bit - all services seem to be starting OK. When it reaches the graphical stage, the screen gives a message "signal out of range" and goes into power save mode.

Can anybody help me - or point me in the right direction.

I would be very grateful - Thanks.

PS I have tried connecting direct i.e. without the KVM - no joy.

[happybunny]

I am neither a hardware expert or linux expert but it sounds like the refresh is to high.

Check out the /etc/XF86Config file. This sets your "xwindows" refresh rates.

There is a menu based gui to do this too, but the command escapes me right now.

When your machine is done booting up and you get that "out of range" message, hit ctrl-alt-F2 or F3 or F4....this will bring you to a shell login which will most likely be in range for you monitor.

Log on and you can move around to edit files.

[happybunny]

redhat-config-xfree86 might work enough for you to configure X thru a gui

[andysdp]

Thanks for your reply Happybunny.

Have tried the ctrl-alt-F2 and have logged in.

tried redhat-config-xfree86 and message back "requires admin privileges but more info needed" then asked for password for root, which I entered and back to powersave mode !

[EnigmaOne]

Yeah, I'm betting that you had your CRT monitor scanning at the high end of the VESA rates. Most LCDs won't handle that type of scan rate.

Easiest thing to do is to re-connect your CRT monitor, get back in, and dig through your /etc/X11/XF86Config-4 file.

Where you probably have something like:

HorizSync 30.0 - 97.0
VertRefresh 50.0 - 180.0

you'll want to modify it to something like:

HorizSync 30.0 - 81.0
VertRefresh 56.0 - 75.0 <--Some LCDs will require '56.0 - 60.0' to artificially force X to use the optimal fv.

Make sure that you keep these within your manufacturer's published specifications for the LCD.

[edit]
Oh Yeah...when you're done editing.
Save and power-down.
Swap your LCD back in and power up.
You shouldn't have an out-of-range signal to the LCD, and can fine-tine your /etc/X11/XF86Config-4 file to your personal preferences.

[bandwidth_pig]

It's most certainly a case of the horizontal and vertical refresh rates not being in synch with your monitor. I strongly encourage you to get out your manual and read the documentation for your monitor. As eluded to, the information you will need will most likely be under the specifications section of the manual (if you do not have a manual go the manufacturers website). You will need both the horizontal and vertical refresh rates. It will be a range...for example 50-90 for one and 60-120 for the other. Once you find this information, you will need to reconfigure X. There are a few ways to go about this. But all methods you have will be text based...as in your current state you can't access a GUI. No big deal. This is real easy. You can either:

1. Edit your XF86Config file by hand using a editor of your choosing (VI or Emacs). I think you will find XF86Config under /etc/X11R6/XF86Config. I'm not in Linux right now or I would check the path. I myself like vi. Find the applicable section in the XF86Config file and enter in your rates yourself. This would be under:

# ************************************************** *******************
*
# Monitor section
# ************************************************** *******************
Section "Monitor"

Identifier "My Monitor"

# HorizSync is in kHz unless units are specified.
# HorizSync may be a comma separated list of discrete values, or a
# comma separated list of ranges of values.
# NOTE: THE VALUES HERE ARE EXAMPLES ONLY. REFER TO YOUR MONITOR'S
# USER MANUAL FOR THE CORRECT NUMBERS.

HorizSync 31-63.9

# HorizSync 30-64 # multisync
# HorizSync 31.5, 35.2 # multiple fixed sync frequencies
# HorizSync 15-25, 30-50 # multiple ranges of sync frequencies
# VertRefresh is in Hz unless units are specified.
# VertRefresh may be a comma separated list of discrete values, or a
# comma separated list of ranges of values.
# NOTE: THE VALUES HERE ARE EXAMPLES ONLY. REFER TO YOUR MONITOR'S
# USER MANUAL FOR THE CORRECT NUMBERS.

VertRefresh 60-75

EndSection


See where it says HorizSync? Right after that you just enter the range from your documentation. Same holds true for down at the bottom where it says VertRefresh and the range (in my case 60-75).

2. Your other option is not too tough either. You can reconfigure X through xf86config. It will prompt you with a series of questions about your setup. You will need to know:

A. What kind of mouse you have (most likely PS2).
B. What your refresh rates are for your monitor.
C. What kind of video card you have.
D. How much memory it has.

There are a couple of other questions you'll be faced with (emulate three mouse buttons, keyboard...etc). If you get stuck I'll help you. Either of these two methods will work.

[EnigmaOne]

I just went back and checked a stock RH9 machine; and it does use /etc/X11/XF86Config instead of /etc/X11/XF86Config-4.

The section you'd be looking for--in a stock RH9 machine--in your /etc/X11/XF86Config file will look like:

Section "Monitor"
Identifier "Monitor0"
VendorName "Monitor Vendor"
ModelName "Monitor Model"
DisplaySize [some numbers here]
HorizSync 30.0 - 107.0
VertRefresh 48.0 - 120.0
Option "dpms"
EndSection

(This is from one of my kids' machines.)

All the previous comments apply.

::: waving at bp ::: Good to see you again.

[andysdp]

bandwidth_pig and EnigmaOne

Thanks guys for you help and advice.

I will get back to you once I have had a chance to digest you postings. I have to go away and learn how to edit these files as this is all new to me. But I will get there in the end! Thanks to you, I now no what has to be done.

Thanks again

[EnigmaOne]

I think you'll be headed in the right direction...best of luck, and let us know how it goes.

....and Welcome to JL. :)

[bandwidth_pig]

Originally posted by andysdp
bandwidth_pig and EnigmaOne

Thanks guys for you help and advice.

I will get back to you once I have had a chance to digest you postings. I have to go away and learn how to edit these files as this is all new to me. But I will get there in the end! Thanks to you, I now no what has to be done.

Thanks again

Ahhh. Thats no trouble. I only use vi myself, but I can get you through this in about two minutes.

1. Change to the directory in question that contains XF86Config: ie cd /etc/X11R6/. Before doing anythign with the file make a backup of it.
cp XF86Config XF86Config.bak

2. vi XF86Config

3. You have just invoked the editor vi on the file XF86Config.

4. Use your arrow key to scroll down to the section I described previously called "Monitors". You'll know it when you see it.

5. Find the area in the section where the hortizonal sync. Arrow your way over to where your old horizontal sync is listed. Now, to edit in vi...you can't just type at will. You need to arrow over to exactly where you want to make your first change and press "d". If you had the cursor over the number 3 in 32, you would have just deleted number three and only be left with 2, if that makes sense. D is for delete. If you hit space, it will delete the next character. Careful with that d key. It's real easy to delete the entire line.

6. When you are ready to type in your new range (even if it is only one number at a time) hit the letter "i". I is of course for insert.

7. Once you are done with the horizontal, hit your escape key. And arrow down to your vertical refresh. Insert and delete as you just did for your horizontal. Just hit "I" and "D" as needed.

8. When you are done, hit ":" and then "wq"

Poof. Your done. A lot of people hate vi because it is not easy to use. But once you get a feel for it, you'll be glad you did as you will find it by default on every Unix system out there...should you be using a machine out and about other than your own :D
Same holds true for Linux. The only Linux distribution that I have found that did not have vi ready right out of the box was Gentoo :rolleyes:
But then I just emerged it during the install anyway :D

[andysdp]

Thanks bandwidth_pig

vi seems cool. Thanks for the lesson. Have manage to view the file. Not edited it yet, as couldn't make a backup !

Tried cp XF86Config XF86Config.bak and received the following message:

cp: cannot create regular file 'XF86Config.bak' : Permission denied

Any ideas ?

What's the best place to look to find "the basics" - it's like working in DOS again !

Thanks

[mdwatts]

Originally posted by andysdp

Tried cp XF86Config XF86Config.bak and received the following message:

cp: cannot create regular file 'XF86Config.bak' : Permission denied


You need to be root for write permissions in /etc.

su -
<root password>

cd /etc/X11

cp XF86Config XF86Config.bak

Also for editing and saving.

Have a look at some of the recent threads in /dev/random as there are a few on commandline basics and good books to purchase. And suggestions on links etc.

[andysdp]

Thanks guys

Screen now working with Red Hat ! Display is a little fuzzy, however I guess I can tweak the refresh values until it is spot on .

I'm a little further along the learning curve !

I much appreciate your patience.

Cheers