Intermittent Monitor

linuxbird · 10-08-2017, 11:53 AM

A three monitor system, where the first monitor is driven by the motherboard and i7-3770k processor, has the first monitor dropping out, and returning back online at random intervals.

I have done a bit of poking, but when the monitor drops offline, it is as if there is no monitor there to the software. So I don't have allot to chase. I have replaced cables, and swapped monitors (they are all identical) but haven't isolated anything obvious.

Does anyone have some ideas as to how I might better isolate and resolve this matter?

fatmac · 10-09-2017, 06:33 AM

Lack of activity putting it to sleep? Automatic screen saver setting?

(Just the sorts of things I'd take a look at, I don't run multiple monitors myself.)

business_kid · 10-13-2017, 03:14 PM

Three monitors? On one machine? Come up with some video details (cards, layout). Most video cards only do 2 monitors. Also post your video config for X and what exactly happens to the monitor. Does X forget it? Does the hardware forget.

When the box is working fine, You can do something like

Code:

# lspci > lspci_good.txt
# lsmod > lsmod_good.txt
# xrandr -q > xrandr_good.txt

Save those. Then when it's misbehaving, repeat using 'bad' instead of 'good'. When you have good and bad, post the output (if any) of

Code:

# diff -u lspci_bad.txt lspci_good.txt
# diff -u lsmod_bad.txt lsmod_good.txt
# diff -u xrandr_bad.txt xrandr_good.txt

And clearly label the outputs and don't swap the file order in the diff commands so there won't be any doubt. We'll see what's going on.

linuxbird · 10-21-2017, 09:29 AM

It appears that one of the monitors is sometimes not recognizing that it has a source. So it appears that I have a toes-up monitor. Ugh. Nec EX231W I will either replace it, or switch to a 4k monitor.

Thanks everyone.