Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
xorg.conf: Is it necessary that I set the monitor sync?
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Desktop Environments
View previous topic :: View next topic  
Author Message
softwind
Tux's lil' helper
Tux's lil' helper


Joined: 03 Jul 2006
Posts: 90

PostPosted: Thu Dec 07, 2006 11:32 pm    Post subject: xorg.conf: Is it necessary that I set the monitor sync? Reply with quote

Is it necessary that I set the monitor sync? By default it is not set. I looked at some other distros, and their monitor sync is not set in xorg.conf either.
Back to top
View user's profile Send private message
DocReedSolomon
Guru
Guru


Joined: 28 Aug 2006
Posts: 419

PostPosted: Thu Dec 07, 2006 11:36 pm    Post subject: Reply with quote

if the frequenzy is OK for you, you dont have to.
are you unsatisfied with the frequencys? or why asking?
Back to top
View user's profile Send private message
softwind
Tux's lil' helper
Tux's lil' helper


Joined: 03 Jul 2006
Posts: 90

PostPosted: Thu Dec 07, 2006 11:57 pm    Post subject: Reply with quote

Well, how can I tell if the frequencies is okay?

I ask because my monitor sometimes gives off this signal. I do not know what this signal means as the monitor manual mentions nothing about it. I asked the tech support, and no surprise, they slapped the "Well... if you are using Linux, then you are on your own" on me.

The signal will stay for a few minutes and then go away. The alternative is to shut off my monitor for a few minutes and then turn it back on.

I am not sure what causes it. But I suspect it is the frequency. I have the frequencies set properly in the monitor section.

Code:

        HorizSync    30-71
        VertRefresh  50-160


I notice nothing visibly wrong when the signal activates. But the the signal is annoying.

Back when I was still using Windows, and trying other distros, this signal did not happen. None of the distros I have tried required me to configure my own monitor as it uses auto-detect. In Gentoo, it requires me to manually configure things. So I thought that I did something wrong or did too much.
Back to top
View user's profile Send private message
johndoe_1995
n00b
n00b


Joined: 27 Oct 2004
Posts: 4

PostPosted: Fri Dec 08, 2006 12:01 am    Post subject: Reply with quote

I'm curious, does the monitor autoconfigure when you run the following as root?
Code:
X -configure

This command will output an xorg.conf file in /root
Back to top
View user's profile Send private message
DocReedSolomon
Guru
Guru


Joined: 28 Aug 2006
Posts: 419

PostPosted: Fri Dec 08, 2006 12:05 am    Post subject: Reply with quote

softwind wrote:
Well, how can I tell if the frequencies is okay?

2 choices:
a) if you check with your monitors manual.
b) if it is OK with your eyes.
softwind wrote:

I ask because my monitor sometimes gives off this signal.

i bet, linux is, or even windows. ACPI is setting your monitor to OFF after xx minutes?
what GUI are you using? KDE?

i bet its just a screenblanker.
btw: it does not do so if you are typing, right?
Back to top
View user's profile Send private message
softwind
Tux's lil' helper
Tux's lil' helper


Joined: 03 Jul 2006
Posts: 90

PostPosted: Fri Dec 08, 2006 12:15 am    Post subject: Reply with quote

johndoe_1995 wrote:
I'm curious, does the monitor autoconfigure when you run the following as root?
Code:
X -configure

This command will output an xorg.conf file in /root

Before I try to run that, I must ask: Is that what automatically configures and overwrites my xorg.conf?

The first time I installed Gentoo, I used a command (I forgot it) that automatically set my xorg.conf and did not go as well as expected. So I ended up reinstalling the whole thing.

What safety measure (what do I need to backup?) can I take before trying that command?

Quote:
a) if you check with your monitors manual.

Huh? Check my monitor manual for what? The frequencies? I mentioned that I have set the proper frequencies. In other words, I have used the frequencies from the monitor manual.

b) if it is OK with your eyes.

Okay with my eyes, but not my ears. The signal activates for a reason...

Quote:
what GUI are you using? KDE?

Fluxbox

Quote:
i bet its just a screenblanker.

Come again? The screen does not change at all.

Quote:
btw: it does not do so if you are typing, right?

It does so too when I am typing. Whether I am computing or not, the signal will activate randomly.
Back to top
View user's profile Send private message
erik258
Advocate
Advocate


Joined: 12 Apr 2005
Posts: 2650
Location: Twin Cities, Minnesota, USA

PostPosted: Fri Dec 08, 2006 12:32 am    Post subject: Reply with quote

i can't say i understand exactly what is meant by 'signal'. however if you mean the picture is somehow not ok...

monitors wear out and break eventually, or the screen gets all blurry and crappy. and maybe they overheat? i prefer the overheatnig explination of why the monitor would do so because it explains also why it would come back eventually.

any evidence to suggest that? like, it always happens about the same amount of time after you turn it on, you notice it gets realy hot, or maybe you decided to cover up all those inconspcuous air vent holes on every side with a blanket or something?

or perhaps you are talking about a sound the monitor emits. is it a very, very high pitched whine? many people with sensitive hearing hear this being produced from CRTs of all kinds, from monitors to tvs to ... some other kind of CRT. if this is your problem, maybe a higher refresh rate would help, or maybe your monitor is particularly loud, or crappy, or maybe really old ... or maybe if you just cant stand the sound that CRTs make, you could just buy an LCD which snice they don't have the need to asclillate magnetic fields are almost certainly guaranteed not to make this sound.

by the way, too low of refresh rates usually have the effect of making the screen image all 'flickery' and some people say causing headaches. personally i find higher refresh rates than 70 to be much more pleasant than 65 or below, and 50 is downright dismal. most modern monitors can do a decent refresh rate at a resolutino that fits your preference.

theoretically (factually, probably) specifying a refresh rate beyond the hardware capabilities of the CRT could nicely ruin it.
_________________
Configuring a Firewall? Try my iptables configuration
LinuxCommando.com is my blog for linux-related scraps and tidbits. Stop by for a visit!
Back to top
View user's profile Send private message
softwind
Tux's lil' helper
Tux's lil' helper


Joined: 03 Jul 2006
Posts: 90

PostPosted: Sat Dec 09, 2006 1:21 pm    Post subject: Reply with quote

Quote:
or perhaps you are talking about a sound the monitor emits.

That is it!

Quote:
many people with sensitive hearing hear this being produced from CRTs of all kinds, from monitors to tvs to ... some other kind of CRT.

No sensetivity. This is the third CRT I owned, and this is the only one I hear sounds from. And only started hearing the signal when I installed Gentoo in it.

I do not hear anything at all from TVs.

Quote:
if this is your problem, maybe a higher refresh rate would help, or maybe your monitor is particularly loud, or crappy, or maybe really old

As mentioned above, I have set the VertRefresh to 50-160. I recall setting something outside the specifications is bad.

The monitor is only a year old.

Quote:
or maybe if you just cant stand the sound that CRTs make, you could just buy an LCD which snice they don't have the need to asclillate magnetic fields are almost certainly guaranteed not to make this sound.

I am not rich enough to let a 1-year-old monitor get dusted as I go shopping for a LCD. So I am looking for a technical alternative.

Quote:
by the way, too low of refresh rates usually have the effect of making the screen image all 'flickery' and some people say causing headaches.

Do not have that happening. Everything is fine visually.

Quote:
most modern monitors can do a decent refresh rate at a resolutino that fits your preference.


Resolution 1280x960
HorizSync 30-71
VertRefresh 50-160

The frequencies is from the specifications. The resolution is the second highest that my monitor can handle.

Setting the resolution anything lower would make me feel like wearing unnecessary glasses.
Back to top
View user's profile Send private message
erik258
Advocate
Advocate


Joined: 12 Apr 2005
Posts: 2650
Location: Twin Cities, Minnesota, USA

PostPosted: Sat Dec 09, 2006 2:37 pm    Post subject: Reply with quote

The refresh rate ranges are usually what's required to set a decent refresh rate, but sometimes it seems to get set a little low, so maybe setting a specific refresh rate for the resolution you're running at would help. You might want to find an entire modeline online somewhere you can use.

Too bad we can't all have nice LCDs huh? I for one, I haven't been able to buy even a new CRT since 2000 ; ) but luckily, it costs money to dispose of them now so lots of people give them away. So what if the console on one of my boxes never shows the color red?
_________________
Configuring a Firewall? Try my iptables configuration
LinuxCommando.com is my blog for linux-related scraps and tidbits. Stop by for a visit!
Back to top
View user's profile Send private message
softwind
Tux's lil' helper
Tux's lil' helper


Joined: 03 Jul 2006
Posts: 90

PostPosted: Mon Dec 11, 2006 4:59 pm    Post subject: Reply with quote

How do I set the refresh rate?

I thought the refresh rate is preset when I choose a resolution.

I have used this manual when configuring xorg.conf and it mentions nothing of the refresh rate.

Is it safe to set a refresh rate outside the recommended for a resolution?
Back to top
View user's profile Send private message
erik258
Advocate
Advocate


Joined: 12 Apr 2005
Posts: 2650
Location: Twin Cities, Minnesota, USA

PostPosted: Mon Dec 11, 2006 5:13 pm    Post subject: Reply with quote

If you want the best graphics quality for your monitor, i recommend trying first to find a modeline for it online. that will have all the exact timings in it.
_________________
Configuring a Firewall? Try my iptables configuration
LinuxCommando.com is my blog for linux-related scraps and tidbits. Stop by for a visit!
Back to top
View user's profile Send private message
Section_8
Guru
Guru


Joined: 22 May 2004
Posts: 477
Location: Arlington, TX, US

PostPosted: Mon Dec 11, 2006 5:21 pm    Post subject: Reply with quote

Does the sound ever happen when you boot a live CD like Knoppix? If it doesn't, you could copy off the xorg.conf file it generates and compare that with yours.
Back to top
View user's profile Send private message
softwind
Tux's lil' helper
Tux's lil' helper


Joined: 03 Jul 2006
Posts: 90

PostPosted: Wed Dec 13, 2006 11:15 pm    Post subject: Reply with quote

What is a modeline? I have looked at the specifications of my monitor and it mentions nothing of modeline.

I tried booting with Knoppix and it emits that sound too when I compute long enough.

Any other ideas?
Back to top
View user's profile Send private message
Section_8
Guru
Guru


Joined: 22 May 2004
Posts: 477
Location: Arlington, TX, US

PostPosted: Thu Dec 14, 2006 12:57 am    Post subject: Reply with quote

ModeLine is a statement in the monitor section of xorg.conf that describes the monitor hardware:

Code:
   # 1152x864 @ 75
    ModeLine "1152x864"    108 1152 1216 1344 1600  864 865 868 900 +HSync +VSync


man xorg.conf documents it.

If you google for it you will find web sites like this: http://www.bohne-lang.de/spec/linux/modeline/
or this: http://xtiming.sourceforge.net/cgi-bin/xtiming.pl
that can calculate it from the vertical/horiz frequencies that should be in your monitor's manual.
Back to top
View user's profile Send private message
softwind
Tux's lil' helper
Tux's lil' helper


Joined: 03 Jul 2006
Posts: 90

PostPosted: Fri Dec 15, 2006 1:41 am    Post subject: Reply with quote

There is no modeline in xorg.conf that looked like the example you have provided.

However, when I booted in Knoppix, I got a modeline from the XF86Config file.

Code:
Section "Monitor"
   Identifier   "Monitor0"
   VendorName   "GSM"
   ModelName   "GSM4366"
   HorizSync 30 - 71 # DDC-probed
   VertRefresh 50 - 160 # DDC-probed
   # These are the DDC-probed settings reported by your monitor.
   # 1280x1024, 75.0Hz; hfreq=79.98, vfreq=75.03
   ModeLine "1280x1024"   135.00 1280 1296 1440 1688 1024 1025 1028 1066 +hsync +vsync
   # 1152x864, 75.0Hz; hfreq=67.50, vfreq=75.00
   ModeLine "1152x864"   108.00 1152 1216 1344 1600  864  865  868  900 +hsync +vsync
   # 1024x768, 85.0Hz; hfreq=68.68, vfreq=85.00
   ModeLine "1024x768"    94.50 1024 1072 1168 1376  768  769  772  808 +hsync +vsync
   # 1024x768, 75.0Hz; hfreq=60.02, vfreq=75.03
   ModeLine "1024x768"    78.75 1024 1040 1136 1312  768  769  772  800 +hsync +vsync
   # 1024x768, 70.0Hz; hfreq=56.48, vfreq=70.07
   ModeLine "1024x768"    75.00 1024 1048 1184 1328  768  771  777  806 -hsync -vsync
   # 1024x768, 60.0Hz; hfreq=48.36, vfreq=60.00
   ModeLine "1024x768"    65.00 1024 1048 1184 1344  768  771  777  806 -hsync -vsync
   # 800x600, 85.0Hz; hfreq=53.67, vfreq=85.06
   ModeLine "800x600"    56.25  800  832  896 1048  600  601  604  631 +hsync +vsync
   # 800x600, 75.0Hz; hfreq=46.88, vfreq=75.00
   ModeLine "800x600"    49.50  800  816  896 1056  600  601  604  625 +hsync +vsync
   # 800x600, 60.0Hz; hfreq=37.88, vfreq=60.32
   ModeLine "800x600"    40.00  800  840  968 1056  600  601  605  628 +hsync +vsync
   # 800x600, 56.0Hz; hfreq=35.16, vfreq=56.25
   ModeLine "800x600"    36.00  800  824  896 1024  600  601  603  625 +hsync +vsync
   # 640x480, 85.0Hz; hfreq=43.27, vfreq=85.01
   ModeLine "640x480"    36.00  640  696  752  832  480  481  484  509 -hsync -vsync
   # 640x480, 75.0Hz; hfreq=37.50, vfreq=75.00
   ModeLine "640x480"    31.50  640  656  720  840  480  481  484  500 -hsync -vsync
   # 640x480, 72.0Hz; hfreq=37.86, vfreq=72.81
   ModeLine "640x480"    31.50  640  656  696  816  480  481  484  504 -hsync -vsync
   # 640x480, 60.0Hz; hfreq=31.47, vfreq=59.94
   ModeLine "640x480"    25.17  640  648  744  784  480  482  484  509 -hsync -vsync
   # Extended modelines with GTF timings
   # 640x480 @ 100.00 Hz (GTF) hsync: 50.90 kHz; pclk: 43.16 MHz
   ModeLine "640x480"  43.16  640 680 744 848  480 481 484 509  -HSync +Vsync
   # 768x576 @ 60.00 Hz (GTF) hsync: 35.82 kHz; pclk: 34.96 MHz
   ModeLine "768x576"  34.96  768 792 872 976  576 577 580 597  -HSync +Vsync
   # 768x576 @ 72.00 Hz (GTF) hsync: 43.27 kHz; pclk: 42.93 MHz
   ModeLine "768x576"  42.93  768 800 880 992  576 577 580 601  -HSync +Vsync
   # 768x576 @ 75.00 Hz (GTF) hsync: 45.15 kHz; pclk: 45.51 MHz
   ModeLine "768x576"  45.51  768 808 888 1008  576 577 580 602  -HSync +Vsync
   # 768x576 @ 85.00 Hz (GTF) hsync: 51.42 kHz; pclk: 51.84 MHz
   ModeLine "768x576"  51.84  768 808 888 1008  576 577 580 605  -HSync +Vsync
   # 768x576 @ 100.00 Hz (GTF) hsync: 61.10 kHz; pclk: 62.57 MHz
   ModeLine "768x576"  62.57  768 816 896 1024  576 577 580 611  -HSync +Vsync
   # 800x600 @ 100.00 Hz (GTF) hsync: 63.60 kHz; pclk: 68.18 MHz
   ModeLine "800x600"  68.18  800 848 936 1072  600 601 604 636  -HSync +Vsync
   # 1024x768 @ 100.00 Hz (GTF) hsync: 81.40 kHz; pclk: 113.31 MHz
   ModeLine "1024x768"  113.31  1024 1096 1208 1392  768 769 772 814  -HSync +Vsync
   # 1152x864 @ 60.00 Hz (GTF) hsync: 53.70 kHz; pclk: 81.62 MHz
   ModeLine "1152x864"  81.62  1152 1216 1336 1520  864 865 868 895  -HSync +Vsync
   # 1152x864 @ 85.00 Hz (GTF) hsync: 77.10 kHz; pclk: 119.65 MHz
   ModeLine "1152x864"  119.65  1152 1224 1352 1552  864 865 868 907  -HSync +Vsync
   # 1152x864 @ 100.00 Hz (GTF) hsync: 91.50 kHz; pclk: 143.47 MHz
   ModeLine "1152x864"  143.47  1152 1232 1360 1568  864 865 868 915  -HSync +Vsync
   # 1280x960 @ 72.00 Hz (GTF) hsync: 72.07 kHz; pclk: 124.54 MHz
   ModeLine "1280x960"  124.54  1280 1368 1504 1728  960 961 964 1001  -HSync +Vsync
   # 1280x960 @ 75.00 Hz (GTF) hsync: 75.15 kHz; pclk: 129.86 MHz
   ModeLine "1280x960"  129.86  1280 1368 1504 1728  960 961 964 1002  -HSync +Vsync
   # 1280x960 @ 100.00 Hz (GTF) hsync: 101.70 kHz; pclk: 178.99 MHz
   ModeLine "1280x960"  178.99  1280 1376 1520 1760  960 961 964 1017  -HSync +Vsync
   # 1280x1024 @ 100.00 Hz (GTF) hsync: 108.50 kHz; pclk: 190.96 MHz
   ModeLine "1280x1024"  190.96  1280 1376 1520 1760  1024 1025 1028 1085  -HSync +Vsync
   # 1400x1050 @ 60.00 Hz (GTF) hsync: 65.22 kHz; pclk: 122.61 MHz
   ModeLine "1400x1050"  122.61  1400 1488 1640 1880  1050 1051 1054 1087  -HSync +Vsync
   # 1400x1050 @ 72.00 Hz (GTF) hsync: 78.77 kHz; pclk: 149.34 MHz
   ModeLine "1400x1050"  149.34  1400 1496 1648 1896  1050 1051 1054 1094  -HSync +Vsync
   # 1400x1050 @ 75.00 Hz (GTF) hsync: 82.20 kHz; pclk: 155.85 MHz
   ModeLine "1400x1050"  155.85  1400 1496 1648 1896  1050 1051 1054 1096  -HSync +Vsync
   # 1400x1050 @ 85.00 Hz (GTF) hsync: 93.76 kHz; pclk: 179.26 MHz
   ModeLine "1400x1050"  179.26  1400 1504 1656 1912  1050 1051 1054 1103  -HSync +Vsync
   # 1400x1050 @ 100.00 Hz (GTF) hsync: 111.20 kHz; pclk: 214.39 MHz
   ModeLine "1400x1050"  214.39  1400 1512 1664 1928  1050 1051 1054 1112  -HSync +Vsync
   # 1600x1200 @ 100.00 Hz (GTF) hsync: 127.10 kHz; pclk: 280.64 MHz
   ModeLine "1600x1200"  280.64  1600 1728 1904 2208  1200 1201 1204 1271  -HSync +Vsync
   # 1920x1200 @ 60.00 Hz (GTF)  hsync: 74.52; pclk: 193.16 MHz
   Modeline "1920x1200" 193.16  1920 2048 2256 2592  1200 1201 1204 1242  -HSync +HSync
EndSection


I am not sure if the above is correct since I see some resolutions that is not supported by my computer specifications.
Back to top
View user's profile Send private message
sonicbhoc
Veteran
Veteran


Joined: 24 Oct 2005
Posts: 1805
Location: In front of the computer screen

PostPosted: Fri Dec 15, 2006 3:38 am    Post subject: Reply with quote

if I were you, I'd back up my xorg.conf (mv /etc/X11/xorg.conf /etc/X11/xorg.conf.old) and run X -configure, and mess around with /etc/X11/xorg.conf to get it the way you want. That's what I did anyway.
_________________
I'm too lazy to keep this stupid signature up to date, so here's something more interesting:
My friend Hetdegon can draw if you ask me.
Now using PClinuxOS on my laptop and Gentoo on my desktop and new laptop.
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Desktop Environments All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum