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Since I mostly work at night I have to be able to reduce the brightness level of my screen, otherwise my eyes wont last for very long. Few days ago I bought a brand new EIZO 2451 monitor to give my eyes the best screen I could find, so I thought...

EIZO 2451 comes with the guarantee that any screenflickering is eliminated. The term "pwv" is used in my country to indicate the monitor is guaranteed free of screen flickering even in levels below 10% brightness. The Eizo monitor officially only supports Windows 7.8.10. It works out of the box however when connected to LM 18.3 Cinnamon. But I do have some screenflickering when I lower the TEMPERATURE settings to 4000K. I didnt see that screenflickering with this new Eizo screen at lower TEMPERATURE settings (4000-5000K) in Windows7.But I do see it in LM 18.3 Cinnamon. I use open source nouveau driver, because my Nvidea graphics card wont funtion in LM18.3. That has never been a problem, the nouvea driver works perfectly.

But now I am pondering what else can I do, to eliminate this screenflickering in LM 18.3 with my new Eizo monitor. I know Eizo wont/cant support Linux, although I havent asked them yet...

There is one setting (RGB) which has NO screenflickering in LM 18.3, but the color is very blueish, (6500K) and it hurts my eyes to look at that setting for too long, because I have to work at night. Those bright RGB settings are more suited for offices during day light hours. All the other settings in which I lower the TEMPERATURE to 4000K setting becomes more prone to screen flickering.

Some people perceive flickering more than others and if the brightness is lowered, then flickering is easier to perceive in an LED monitor.

I assume you checked the cable for tightness first. Then tried disconnecting and reconnecting the cable at both ends. Also, the video card can be checked that it is seated fully.

Your monitor is unusual for having VGA, DVI, HDMI and DisplayPort connectors. How is it connected now? Did you try switching to a different one?

Instead of changing the temperature, you can try changing the gamma setting on the monitor, or you can open the Terminal and type: xgamma -gamma .9. Then test reducing the value .1 at a time.

The Nvidia driver installation can be investigated. Open the Terminal, use this command and post the output: inxi -SCGx

As a last resort, you can raise the temperature setting and wear blue-light-blocking glasses.

This is my System:
Host: gcee Kernel: 4.13.0-45-generic x86_64 (64 bit gcc: 5.4.0)
Desktop: Cinnamon 3.6.7 (Gtk 3.18.9-1ubuntu3.3)
Distro: Linux Mint 18.3 Sylvia
CPU: Dual core AMD Athlon 7450 (-MCP-) cache: 1024 KB
flags: (lm nx sse sse2 sse3 sse4a svm) bmips: 9600
clock speeds: max: 2400 MHz 1: 2400 MHz 2: 2400 MHz
Graphics: Card: NVIDIA C77 [GeForce 8200] bus-ID: 02:00.0
Display Server: X.Org 1.18.4 drivers: nouveau (unloaded: fbdev,vesa)
Resolution: 1920x1080@60.00hz
GLX Renderer: NVAA
GLX Version: 3.0 Mesa 17.2.8 Direct Rendering: Yes

Roblm thanks for your tips.Above are my videospecs of my linux system mentioned.

You are right that lots of connections are available at my monitor. Unfortunately my pc only has hdmi and dvi connections. The monitor is currently connected through hdmi and that hdmi cable DID give good quality when I tested the new Eizo monitor under Windows7. I will want to try your tip of changing the cable anyway, one never knows.

In Windows7 I could choose different frequencies in the settings. Linux automatically chooses 60 Hz, which seems to be the best choice. The higher, the better right?
I can mess with the frequencies and other stuff on my monitor in linux if I connect through vga, but that is pre historic picture quality compared to hdmi connection.

I already have tried changing the gamma, but that has no effect unfortunately. But I will trie your tip of changing the gamma in the terminal. Never knew that that was possible. Great tip!

By the way, I thought that the RGB setting didnt give any screen flickering in linux, but I was wrong. The RGB setting is THAT bright that I just didnt notice it at first in linux. So therefore ALL the monitor settings give screen flickering, although in one setting it is just more noticeable than in another setting.

Eizo has got some hybrid system by which they claim NONE screen flickering is achieved. Maybe this system is not supported in lInux? Is it worth trying to change to LinuxMint Mate? That is known to have better hardware support, or doesnt that matter when my Nvideo card isnt supported?

newbie serena wrote: ⤴Sat Jun 30, 2018 4:53 pm You are right that lots of connections are available at my monitor. Unfortunately my pc only has hdmi and dvi connections.

So you should be able to test a DVI to DVI connection.

newbie serena wrote: ⤴Sat Jun 30, 2018 4:53 pm In Windows7 I could choose different frequencies in the settings. Linux automatically chooses 60 Hz, which seems to be the best choice. The higher, the better right?

To check if the monitor supports higher refresh rates, use this command and post the output: xrandr --prop
It probably won't at 1920x1080.

newbie serena wrote: ⤴Sat Jun 30, 2018 4:53 pm Eizo has got some hybrid system by which they claim NONE screen flickering is achieved. Maybe this system is not supported in lInux? Is it worth trying to change to LinuxMint Mate?

Once the monitor gets the video signal from the video card, then the rest of the image processing will done by the monitor, so the operating system should not have any effect. But it"s easy to test the Live Installation DVD/USB.

The GeForce 8200 release date was January of 2008. Compared to the newer video cards out today, it’s pretty weak. Check this link: https://www.videocardbenchmark.net/gpu. ... Force+8200

Would a newer card solve the flickering. Perhaps, but I don’t know for sure. Do you have any other PCs with newer video cards to test?

Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
VGA-1 disconnected (normal left inverted right x axis y axis)
scaling mode: None
supported: None, Full, Center, Full aspect
color vibrance: 150
range: (0, 200)
vibrant hue: 90
range: (0, 180)
link-status: Good
supported: Good, Bad
HDMI-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 528mm x 297mm



dithering depth: auto
supported: auto, 6 bpc, 8 bpc
dithering mode: auto
supported: auto, off, static 2x2, dynamic 2x2
scaling mode: None
supported: None, Full, Center, Full aspect
color vibrance: 150
range: (0, 200)
vibrant hue: 90
range: (0, 180)
underscan vborder: 0
range: (0, 128)
underscan hborder: 0
range: (0, 128)
underscan: off
supported: auto, off, on
link-status: Good
supported: Good, Bad
1920x1080 60.00*+ 50.00 59.94
1920x1080i 60.00 50.00 59.94
1680x1050 59.88
1600x900 60.00
1280x1024 60.02
1280x800 59.91
1280x720 60.00 50.00 59.94
1024x768 60.00
800x600 60.32
720x576 50.00
720x480 60.00 59.94
640x480 60.00 59.94
720x400 70.08

Thanks alot for the tips. I will try the live DVD first to find out if it makes any difference.

Amazing link you posted about my video card. Those other cards have values well into the thousands. My old nvidea card has got a value below 100 !

But according to you the video signal once it leaves the pc and arrives at the monitor, should be totally controlled by the monitor.

I tinkered a bit with different settings on my Eizo EV 2451 monitor and I definitely found out that when I lower brightness or contrast level the flikcering aggravates. Just as seems to be the case with most monitors. But Eizo guaranteed customers a flicker free experience, see below.

Here is what Eizo tells customers about their anti flickering technique:

" To help protect your eyes, EIZO has developed a hybrid technology to control the backlight. This combines the benefits of the otherwise standard PWM (pulse width modulation) and DC (direct current) control. PWM control uses refresh rates of 18 kHz. The result: a flicker-free viewing experience Flickering is reduced down to absolute freedom from flickering, without impairing image quality or colour stability. In addition, the brightness can be set to less than 1% of the maximum value in darkly lit rooms. The benefit: Your screen remains free from glare even under these conditions. "

I tested the screen flickering with the LM18.3 live dvd running on my system. No difference. Same results with screen flickering in lower brightness levels.

Gamma levels seem to worsen or better the screen flickering as well, but only if brightness levels are already lowered. The main cause of screen flickering still seems to be related to the lowering of brightness level and or contrast level. Which it should NOT be, according to Eizo's EV 2451 "guarantee".

Because I work at night I am used to lower levels of light in my room. I adjust the brightness of my monitor according to the lower levels of my room to prevent my eyes from detoriating from glaring contineously at a very bright screen.

I do wanna try another connnetion cable. Any tips on buying a good quality dvi or hdmi cable?

newbie serena wrote: ⤴Sun Jul 01, 2018 2:58 am I do wanna try another connnetion cable. Any tips on buying a good quality dvi or hdmi cable?

I just said to disconnect the HDMI cable at both ends and then reconnect it, not buy another one. You can also try gently wiggling the cable near it’s connection, to rule out a faulty connection.

For the DVI cable, look for quality build, conforms to the DVI DDWG standards and some others say are shielded, so they are less susceptible to interference.
The Single-link DVI cables support up to a 1920×1200 resolution, but Dual-link DVI supports 2560×1600 but are more expensive. Right now you only need a Single-link cable, unless you use higher resolutions over DVI in the future.

You don’t need to buy expensive cables. One brand of quality and low price cables that I’ve seen others recommend is MonoPrice:
https://www.monoprice.com/Category?c_id ... nk-2470763

Here is another:
https://www.amazon.com/AmazonBasics-DVI ... LQ67NVPFZA

The monitor does not support a higher refresh rate than 60 Hz when using the native resolution.

You may just have very sensitive eyes. Did you ask your wife or someone else if they could see the flickering?

You could also test manually setting the color temperature. There may be a User setting. That’s what I do. I have Red set to 60, Green set to 50, and Blue set to 30. Lowering Blue also reduces the brightness, so you won’t have to lower the Brightness setting as much. I find the screen more comfortable to view this way than if I select the Warm preset temperature.

Thanks for your tips!

I have tried wiggling at the hdmi cable, disconnected it too, but to no effect. No difference in screen flickering.

Your temperature tip was very helpful though. Great change in perception of screen flickering. I have 10 different temperature settings and I found several that have the least flickering combined with lower levels of blue light.

I have also found a test site online for monitors. It mentioned several insightful facts and some good tests. ( I will post link to it later on perhaps). The end result of all these tests is that probably my screen flickering cant be altered positively, besides some changing the settings. Although there seems to be some hardware that can influence the voltage. In the end it is a voltage problem which is inherent to all monitors. All monitors flicker, the ones below 19 inch, seem to have a different mechanism by which flickering can be controlled better by hardware. With larger screens that is no longer possible and it is done with software, with a lesser effect of combatting screen flickering.

You are right about me being more sensitive to screen flickering, because I work in low level light surroundings and therefore I tend to notice screen flickering quicker than in daylight surroundings. When I set the monitor to full contrast and brightness in RGB standard setting the screen flickering is barely noticeable. This monitor was designed for office use in bright light surroundings. But in lower brightness level this monitor shows the ever present screen flickering better.

We will see how and if I get used to it. If not I will change the monitor which is a good monitor for all the other qualities it has.