#1 2018-02-24 00:49:58

tuia
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Overclocking your monitor

I recently found out it is easy to overclock your monitor, either in Linux or Windows. The purpose of overclocking your monitor, is you can increase the frames your monitor displays to match your graphic cards frame rate, giving an overall smoother gameplay without any stuttering. Usually most monitors are at default 60 Hz refresh rate, and can be overclocked to 75 Hz or more. Please note, that overclocking can shorten the life span of your monitor or even damage it. You do it at your own risk.

In Linux you can overclock your monitor  with the help of xrandr tool. I have a malfunctioning 24'' BenQ monitor, model GL2460HM, default resolution 1920x1080 at 60 Hz, and could, by trial and error, increase it to 82 Hz at 1920x1080. I followed this guide: https://github.com/kevinlekiller/linux_ … erclocking

Basically, you first compile cvt12, which is an improved version of cvt, to give reduced blanking timings. You type your desired resolution and refresh rate:

./cvt12 1920 1080 75 -b

-b switch is to calculate for reduced blanking timings, modern LCDs use it.  The output for my monitor is:

# 1920x1080 @ 75.000 Hz Reduced Blank (CVT) field rate 75.000 Hz; hsync: 83.925 kHz; pclk: 167.85 MHz
Modeline "1920x1080_75.00_rb2"  167.85  1920 1928 1960 2000  1080 1105 1113 1119 +hsync -vsync

Then, with xrandr you create a new mode line:

xrandr --newmode "1920x1080_75.00_rb2"  167.85  1920 1928 1960 2000  1080 1105 1113 1119 +hsync -vsync

After, you add the mode and output it to your display connection:

xrandr --addmode HDMI1 1920x1080_75.00_rb2
xrandr --output HDMI1 --mode 1920x1080_75.00_rb2

That's it! Your monitor blanks and you should have a higher refresh rate. If it goes out of range and no image is displayed, you have to reboot your computer or you can add a safe resolution command as explained here: https://wiki.archlinux.org/index.php/xr … esolutions

xrandr --output HDMI1 --mode 1920x1080_75.00_rb2 && sleep 5 && xrandr --output HDMI1 --mode 1920x1080_60.00

It will revert back to default 60 Hz after 5 seconds of new refresh rate.

After you test and find the desired resolution and refresh rate, you can make those changes kick in after you login to your Linux distro. This procedure is specific to your display manager. I use LXDM and Xfce as desktop environment. I added to /etc/lxdm/PostLogin:

xrandr --newmode "1920x1080_82.00_rb2" 183.99  1920 1928 1960 2000  1080 1109 1117 1123 +hsync -vsync
xrandr --addmode HDMI2 1920x1080_82.00_rb2
xrandr --output HDMI2 --mode 1920x1080_82.00_rb2

Here is the proof my monitor is running at 82 Hz:
2169194Screenshot_2018-02-24_10-27-11.png

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#2 2018-02-24 06:23:42

ABAS
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Re: Overclocking your monitor

I got confused , how a plug and play device can be modified from somewhere else , with HDMI cable? Impossibiru

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#3 2018-02-24 10:02:35

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Re: Overclocking your monitor

It requires the EDID of the display device to be modified and loaded onto the EPROM.  Really not for the faint hearted you can seriously mess up your displays doing this but it does work.

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#4 2018-02-24 10:49:42

tuia
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Re: Overclocking your monitor

You don't need to edit the EDID of the display, unless you want to make permanent changes. You can use a program in Windows called CRU. More on that later.

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#5 2018-02-24 11:00:04

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Re: Overclocking your monitor

But that is what the program will do, it will replace the EDID with a fake EDID to fool it into running at higher frequency.

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#6 2018-02-24 11:04:55

tuia
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Re: Overclocking your monitor

No, it will automatically edit some Windows inf files that override EDID to allow custom resolutions and refresh rates, that way you can easily test your monitor. You can read more information in the webpage of CRU.

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#7 2018-02-24 11:36:25

tuia
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Re: Overclocking your monitor

A note of warning, if you increase the refresh rate of your monitor too high and no image is displayed,  you have to reboot your computer and start Windows in Safe Mode (press F8 key before Windows boots). Open CRU.exe and delete that resolution entry. Reboot again and it defaults back to original refresh rate.

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#8 2018-02-24 20:00:47

Arkos
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Re: Overclocking your monitor

...

You can do it with Nvidia Control Panel also in Windows.

Add a custom resolution with the desired RefreshRate. The good thing, it will be tested for success before you can save it.

This "CustomResolution" will be written in the driver from Windows. This is the reason why it works. (PnP).

...

How to with nVidiaControlPanel

https://www.gamersnexus.net/guides/1674 … fresh-rate

or

https://www.windowscentral.com/how-over … pc-monitor

and

an older Thread, but good to see how to with CRU

http://www.overclock.net/forum/44-monit … nitor.html

...

Btw. For AMD GraphicCards you can add CustomResolutions too via the AMD GracaDrivers Control Panel

...

Also with IntelHDGraphics it's possible via IntelDriverControlPanel

http://www.overclock.net/forum/44-monit … nitor.html

...

At the end. There's a 50/50 Chance, that your some year old LED Monitor, which has also an VGA Port supports originally 75Hz, but only if you connect it over VGA Port. It works also if you use an 24+5 DVI to VGA Adapter on your Graficcard, but the Cable (MonitorSide) must be on VGA Port.

...

Last edited by Arkos (2018-02-24 20:15:28)

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#9 2018-02-24 21:20:27

Black Mamba
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Re: Overclocking your monitor

Can I underclock my clock while clocking my underclocking clock?

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#10 2018-02-24 21:29:20

Arkos
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Re: Overclocking your monitor

...

Ähh, y... wait... hmm, ... nope.

Don't smoke weed and overclock, Mamba big_smile

...

Last edited by Arkos (2018-02-24 21:33:18)

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