On Wed, Oct 07, 2015 at 01:26:32PM +0200, Johannes Stezenbach wrote: > On Tue, Oct 06, 2015 at 11:04:53PM -0400, Alex Deucher wrote: > > On Tue, Oct 6, 2015 at 11:10 AM, Johannes Stezenbach <js@xxxxxxxxx> wrote: > > > > > > I have a NEC EA244WMi monitor connected to an Asus P8H77-V > > > mainboard with Ivy Bridge Core i5-3550 via DVI. > > > If DPMS suspend is enabled (by xscreensaver, or for testing by > > > "xset dpms force off/suspend/standby"), the monitor > > > enters standby mode but wakes up every 10...30 seconds for > > > 6 seconds to display a "DVI-D: no signal" message. > > > > Some monitors periodically scan all of their inputs if they are not > > actively being driven by anything to try and automatically switch to > > the connected input. When the monitor scans the DVI input, it sees > > load on the pins and turns on, only to realize it's not getting a > > signal and then turns off. If your monitor has an option to turn off > > input probing, that might help. > > It's not like I didn't try to twiddle just about every > available menu item, and also used the monitor's > "Reset to Factory Defaults" to no avail. > However, while trying again I found a hidden menu item > which is only available during the short time the > "No Signal" message is displayed, where the left/right > touch buttons open a "Scan Time" setting with "Normal" > and "Slow" options. After I changed it, the issue was > solved. I changed it back and the issue doesn't reproduce. > So it looks some internal configuration of the monitor > was messed up and is now fixed by twiddling the hidden > menu item. "Scan Time" is not documented in the manual > nor is there an indication in the "No Signal" popup. > > Case closed. And I just came back to see the monitor doing the wakeup cycling again. To try something differerent I unplugged the charger of the laptop sitting nearby in suspend. Bingo! So it looks like an EMI issue. I tried a few times and could reproduce twice and then no more :-( Now the monitor wakes up once every 5min or so... Which brings me back to a previous question: > maybe it is some floating signal line causing the > monitor to misdetect activity? Does the Intel hardware have the capability to switch the DVI signal lines from high-z to ground during DPMS suspend, and if so, does the driver do the right thing? Obviously I have no clue about DVI and intel-gfx, but I thought to ask anyway. Johannes _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
