Monitor Intermittent Blacking Out/Syncing

Hello, LmStearn

Welcome to the Microsoft Community.

It sounds like what you're experiencing is an intermittent problem that can be caused by a number of factors, especially when two different devices and monitors are involved.

First of all, thank you for sharing some information, as the issue you mentioned may be a bit complicated as it involves multiple devices as well as third-party devices, etc., I'll start with some general troubleshooting suggestions for you from a Windows system level, hopefully that will be helpful:

1. Cable and Connection Problems

HDMI/DisplayPort cables: Since you are using two monitors, make sure the cables are in good condition and firmly connected. If the cables are damaged or loose, it may cause signal interruption and hence a black screen.

Try replacing the cable: You can try replacing the monitor cable to see if the problem persists. This will rule out the possibility of a damaged cable.

2. Problems with the monitor itself

TV (Kogan) monitors: Older TV monitors may be less compatible with computers, especially in terms of resolution and refresh rate. TVs usually do not process signals as well as dedicated monitors.

Resolution/Refresh Rate Mismatch: Make sure your computer's output resolution and refresh rate match your TV monitor. For example, a Kogan TV has a resolution of 1366x768; if the computer output is too high, the monitor may not be able to synchronize the signal properly.

Test the Kogan TV alone: to further troubleshoot the problem, you can connect a device using only the Kogan TV and see if the problem persists. If the problem does not occur, it may indicate a compatibility issue between the Evnia monitor and the Kogan TV.

3. Graphics card and driver issues

Outdated or conflicting drivers: If you don't have problems with Windows 10, an update or new driver may be causing the problem. Make sure your graphics card drivers are up-to-date by checking the drivers for both integrated and discrete graphics cards.

Check graphics card settings: Certain settings in the graphics card control panel (such as refresh rate, dynamic resolution, or display scaling) can cause problems, especially when using two different types of monitors. You can reset these settings or try adjusting different settings.

4. Power settings or sleep mode

Power Saving Mode: Check your power settings to make sure that hibernation or power saving mode is disabled for your monitor and graphics card. These features can sometimes cause a black screen, especially if the computer or monitor “goes to sleep” and then fails to wake up properly.

Windows 11 issues: Sometimes newer versions of Windows (such as Windows 11) may have compatibility issues with certain monitor configurations. Make sure your Windows system is up-to-date and check for known display issues related to hardware combinations.

5. Interference or compatibility issues

Graphics card conflicts: If there are multiple graphics cards in your system, or integrated and discrete graphics cards co-exist, make sure you use the correct graphics card for each monitor. Sometimes Windows may switch between graphics cards, causing the monitor to not display correctly.

Connect the monitors to different devices: Since you mentioned that both monitors are having problems on different devices, you can try connecting the monitors to other systems or configurations to see if the same problem still occurs so that you can rule out the cause of the devices themselves.

6. Testing

Test each monitor individually: since the problem is affecting both monitors at the same time, it's worth testing each monitor separately to see if one of them is more prone to the problem.

Check the Event Viewer: you can open Windows' Event Viewer to see if there is an error or warning message associated with the black screen when it occurs. This may help you understand if it's a driver or hardware issue.

If you've ruled out some of these possibilities and the problem persists, you may need to try replacing the graphics card or other device configurations in order to further isolate the problem.

Best regards

Bobhe | Microsoft Community Support Specialist

Thanks, will try the single monitor arrangement to test, the TV is connected via HDMI, the main is through DP.

Edit: The Kogan was removed, no change! After changing the resolution back to 766p, there was even a bit of flickering.

The sync event is unusual in its short duration, compare to cases of changing resolution for a monitor, the blackout is at most half in duration. And the frequency, why does it happen only after around two hours of regular desktop activities, and then in another hour or two? As you say, the logs are sure to reveal something, but where, and what to look for?

Edit: The correct driver was migrated after OS upgrade 18/1, the event logs for the monitor show no errors or warnings.

Device DISPLAY\PHLC272\5&33e57c25&1&UID256 was started.

Under certain conditions, usually when the main monitor is active, switching (on-screen) the TV to the PC HDMI port sends the TV into a sync spin, cured by switching it to another port, then back where this time the desktop shows.

Also tried the drivers from their support page, the inf files of the same name were not present, so it's possible Windows used a more generic model. Will just installing the inf (to oem0.inf) make a difference though, the Radeon Adrenaline driver interface doesn't seem to care all that much.

Edit: The driver files at the site are the same as the originals. The driver for the Kogan TV is the 2006 Generic Monitor version. (No logged errors for that either.)

Had a check around some other threads, for example this one, elsewhere there seems to be mention of DP being not so reliable, especially in combinations with HDMI.

Do use hibernate often, and yes there are issues with dual monitors, so will again check power plan settings, currently it's Bitsum's "Balanced: Better Battery life Overlay." The power plan settings for GPU/monitor only contain the option "Turn monitor off after XX minutes", there are no options related to sleep states, none in Adrenaline either. It does have things like "HDCP support" and "HDMI Link Assurance" enabled for both monitors, could try disabling those for affected monitors.

Also on the to-do list is to ensure any power related settings in the UEFI are not the cause either.

Edit: Nothing relevant for "power" or "monitor" at their FAQ, except for setting up a buzzer.

Edit2: Did end up changing to another DP port on the monitor, things seem to have improved since, so it's now a question of how long to the next syncing. In any case, a decision has to be made to initiate monitor replacement under warranty.

Something else returned to memory, this time on the HP Elite 600 G9 i5 SFF with a different monitor, a VX2728-2K. This one works on a DP => DP slot, now attach another DP => VGA (or other) cord connector into the second UHD770 DP slot, and leave the other end unconnected. Got the above mentioned black out for a second or two every so often, until the second cable was removed.

The OP could be related to a more general issue using a second configured DP socket on devices.

Right, so everything was fine until the Kogan was re-attached, and booted out of hibernation. Then got just one sync. So to repro it's either the second monitor or hibernation, or both, but given the nature of the bug, the money is on hibernation. and DisplayPort. The monitor doesn't have a DP deep sleep option, perhaps the driver is looking/polling for it ?

Another possibility is the DP cable, currently using the stock that came with the monitor. This user had better performance with a DP 1.4 repeater.

Edit: With more GPU activity, e.g. two or more videos running concurrently, the syncing happens much more frequently.