<div dir="ltr">On Mon, Aug 29, 2016 at 8:16 PM, George Hunt <span dir="ltr"><<a href="mailto:georgejhunt@gmail.com" target="_blank">georgejhunt@gmail.com</a>></span> wrote:<br><div class="gmail_extra"><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">I do most of my testing of real hardware, and came across the VGA problem also, I've migrated to using the <span>hdmi</span> input to my monitor, and dongles that translate to <span>hdmi</span>. And I'm able to swap the monitor cable indiscriminately</div></blockquote><div><br></div><div>Cool to have that affirmative result: even if we learned in Bellingham, WA (LinuxFest Northwest) late April that HDMI also needs to be inserted during NUC bootup (often? always? sometimes? anyway demonstrated by Tom Gilliard's main NUC 4 months ago!)<br><br>For those of us living in the dark-ages-of-VGA (thru no choice of our own, funds are limited ;) here a few (final?) concrete tips/results on this fragile CentOS support for VGA: (compared to Fedora 22 etc)<br><br></div><div>- 4 Different Screens were tested (4 diff manufacturers, some genuinely modern) and the result is essentially the same in all 4 cases: VGA video rarely if ever re-appears if your VGA cable (or Mini DisplayPort adapter cable) is disconnected after boot, no matter how briefly?<br><br></div><div>- Fun Curiosity: you can reliably pull the power cable out of the LCD screen (or power cycle the LCD monitor with its own ON/OFF button) and VGA video *will* quite survive amazingly, promptly re-appearing on screen, anytime later when the monitor's power (or power cord) restores electricity!<br><br></div><div>- Bonus Trivia: if the VGA cable is disturbed/disconnected-then-reconnected while the monitor's off, video will NOT subsequently re-appear when the monitor is later powered on. How on earth "God Knows" that the video cable was briefly disconnected-then-reconnected to the monitor while the monitor itself was off, I have no absolutely no clue..but then again I don't know enough about the VGA protocol to attribute this entirely to Voodoo ;-)<br></div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div class="gmail_extra">.On Mon, Aug 29, 2016 at 3:59 PM, Adam Holt <span dir="ltr"><<a href="mailto:holt@laptop.org" target="_blank">holt@laptop.org</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><span>On Mon, Aug 29, 2016 at 5:50 PM, James Cameron <span dir="ltr"><<a href="mailto:quozl@laptop.org" target="_blank">quozl@laptop.org</a>></span> wrote:<br></span><div class="gmail_extra"><div class="gmail_quote"><span><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Only tested one monitor? Try another; the EDID communication path<br>
over VGA could have problems, or the data in monitor Flash unusual.<br></blockquote><div> <br></div></span><div>I tried a different brand of LCD monitor, and the problem remains:<br><br>Fedora 22 NUC allows re-attaching of the VGA cable every time, whereas both CentOS NUC's are highly intermittent (the VGA cable fails to show any video upon re-attachment, the vast majority of the time).<br><br>In hindsight, the other LCD monitor (tested across all 3 NUC's) behaves very much the same way. Perhaps 10% of the time (or less) video re-appears, sometimes triggered by starting/leaving X Windows using Ctrl-Alt-F1 or Ctrl-Alt-F2 (or running "reboot" from ssh, on any machine that was running X Windows at the time, causing video to suddenly re-appear during the shutdown process) but regrettably on both CentOS 7 NUC's (NUC6i3SYH & D34010WYKH) I haven't found any repeatable pattern that permits video to be usefully restored (without a full reboot!)<br><br>PS Problem occurs independent of CentOS 7 NUC's that are running X Windows and those that are not. I mention X Windows only because leaving X / re-entering X seems to (sometimes) facilitate recovery of the video signal in certain not-quite-repeatable situations.<br></div><span><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
Also check age of monitor. Mix not old and new wineskins.<br></blockquote><div><br></div></span><div>The earlier test monitor's from the prior decade it's true, but this newer test from a much more recent vintage ;) <br></div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
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