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refresh rate

4 posts · originally from https://geek.digit.in/community/threads/refresh-rate.8733/

S
sweetvenom Original post #1
Apr 23, 2005 at 9:28 AM
How do we change the refresh rate of the monitor in Red Hat Linux 9.0?
P
pradeep_chauhan #2
Apr 23, 2005 at 9:45 AM
open the configration file found at the folloing location

#vi /etc/X11/xorg.conf

Now scroll down to the monitor section and you will see something as seen below


Identifier "dell"

# 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 31.5 - 57.0

# 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 50-100


edit the existing value and add the desired refresh rate supported by your monitor.

There are also some utilites available to do this via some gui setup.
S
sweetvenom #3
Apr 23, 2005 at 9:59 AM
Linux recognises my monitor as LG 700B instead of LG 700E. My display is set at 1024x768 @ 60HZ. I want to change it o 1024x768 @ 85 Hz.
cool_dude_prav
cool_dude_prav #4
Apr 23, 2005 at 10:01 AM
I believe that you can choose your own Refresh Rates(within manufacturer's limits though) using a proggie called gtf

I shall explain it here..

Say for example, you want it to be 640*480 @ 75Hz.

:arrow: Install gtf (dunno how its done on RH :wink: )

:arrow: You can use the following command : gtf <vertical size> <horizontal size> <refresh rate>
Code: 
gtf 640 480 75

:arrow: It will give an output as 2 lines...
Code: 
# 640x480 @ 75.00 Hz (GTF) hsync: 37.65 kHz; pclk: 30.72 MHz
  Modeline "640x480_75.00"  30.72  640 664 728 816  480 481 484 502  -HSync +Vsync

:arrow: Paste these 2 lines in your xorg.conf(dont forget to backup) in the monitor section

Code: 
Section "Monitor"
	Identifier	"Generic Monitor"
	HorizSync	31-101
	VertRefresh	60-160
EndSection

will now become

Code: 
Section "Monitor"
	Identifier	"Generic Monitor"
	HorizSync	31-101
	VertRefresh	60-160
        # 640x480 @ 75.00 Hz (GTF) hsync: 37.65 kHz; pclk: 30.72 MHz
        Modeline "640x480_75.00"  30.72  640 664 728 816  480 481 484 502  -HSync +Vsync
EndSection


Hope it helps...

BTW Source from an Ubuntu support forum... ;)

Cheers!!!

] K8)8)L [