Loading...
Loading...
A monitor may experience intermittently going black (blanking) when connected to a Dell docking station using HDMI, USB Type-C, or DisplayPort (DP) output. This is not limited to Dell branded monitors. This issue may also be reported on third-party monitors.
There are several possible causes and solutions that you can try: Check your cables. Confirm that your cables are properly connected and securely plugged in. Loose connections can cause intermittent blanking. Outdated drivers can cause compatibility issues and intermittent blanking. Ensure you are on the latest graphics driver for the attached device and dock model. Check the Drivers & Downloads page from the Support Site for the monitor model for any recent firmware updates. If the external monitor continues to intermittently blank out for 3 to 4 seconds, this may be a result of Display Stream Compression (DSC) being enabled.
Updating the Dell Dock WD19 or Dell Thunderbolt Dock WD22TB4 to firmware version 01.00.36, 01.00.20 or later resolves the issue. To download and install the firmware, go to: Support for Dell Dock WD19 Drivers & Downloads Support for Dell Thunderbolt Dock - WD22TB4 Drivers & Downloads Once the firmware update is installed on the docking station, you can Manually Enable DSC Using the Registry Key . Alternatively, Dell will roll back the DSC change in a future update to the video driver, enabling DSC by default. A video driver workaround was previously implemented. For more information about the limitations and changes from the driver workaround, reference Resolution Changes . Users may observe different resolution support after applying this workaround when connecting to certain docks. For more information about Display Stream Compression (DSC), reference What is Display Stream Compression? Manually Enable DSC Using the Registry Key Caution: If done incorrectly, modifying the Windows Registry can lead to data loss or operating system corruption. Dell Technologies recommends that you back up data before proceeding with any Windows Registry edit. It is also recommended that a full backup of the Windows Registry is made before starting the edit. See Windows registry information for advanced users for additional information. Location: [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0000] Registry entry to update: "DPMstDscDisable"=dword:00000000 Location: [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0001] Registry entry to update: "DPMstDscDisable"=dword:00000000 Location: [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0002] Registry entry to update: "DPMstDscDisable"=dword:00000000 Resolution Changes If the video driver workaround was installed, you may see resolution options change on your external displays, depending on your configuration. Table 1: Non-TBT host (2*DP lanes) Condition Triple Display Quad Display (Daisy chain from DP) HBR3 with DSC ON DP+DP+MFDP/HDMI: 3*QHD (2560*1440 at 60 Hz) DP+DP+HDMI/MFDP: 3*QHD at 60 Hz+1*1280*720 at 60 Hz HBR3 with DSC off (12.9 Gbps) DP+DP+MFDP/HDMI: 3*FHD (1290*1080 at 60 Hz) DP+DP+HDMI/MFDP: 4*1280*1024 at 60 Hz Table 2: TBT host (2*DP lanes) Condition Triple Display Quad Display (Daisy chain from DP) HBR3 with DSC ON DP+DP+MFDP/HDMI: 3*4k60Hz DP+DP/HDMI/MFDP+TBT: 2*4k 60 Hz+1*QHD 60 Hz DP+DP+HDMI/MFDP+TBT: 3*4k60Hz+1*4k30Hz/1*QHD60Hz HBR3 with DSC off (32.4 Gbps) DP+DP+MFDP/HDMI: 1*4k60Hz+2*QHD60Hz DP+DP/HDMI/MFDP+TBT: 2*4k60Hz+1*QHD60Hz DP+DP+HDMI/MFDP+TBT: 4*QHD60Hz Table 3: HD22Q dock Condition Single Display Dual Display Triple Display Quad Display (Daisy chain from DP) HBR3 with DSC ON DP:8K (7680x4320) at 60 Hz HDMI:4k60Hz or 4k120Hz or 8k30Hz HDMI+DP: 2*rk60Hz HDMI+DP&DP (daisy chain): 3*QHD60Hz HDMI+DP&DP&DP (daisy chain): 4*QHD60Hz HBR3 with DSC off (32.4 Gbps) DP:4k30Hz HDMI+DP 2*QHD60Hz HDMI+DP&DP (daisy chain): FHD60Hz+2*1280x720@60Hz HDMI+DP&DP&DP (daisy chain): FHD60Hz+3*1280x720@60Hz What is Display Stream Compression? Display Stream Compression can reduce the bandwidth required to transmit high-resolution video signals by compressing the video signal to reduce the amount of data that must be transmitted without compromising the image quality. When DSC is enabled, the compression ratio varies depending on the resolution and refresh rate of the video signal being transmitted. In general, higher resolutions and refresh rates require higher compression ratios to maintain the same level of image quality. As a result, enabling DSC can increase the maximum resolution and refresh rate that can be supported over a given bandwidth. DSC can also have some drawbacks. For example, some monitors may not be fully compatible with DSC. This may cause display issues or blanking.
Click on a version to see all relevant bugs
Dell Integration
Learn more about where this data comes from
Bug Scrub Advisor
Streamline upgrades with automated vendor bug scrubs
BugZero Enterprise
Wish you caught this bug sooner? Get proactive today.