-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 My system is running a fresh install of Stretch (AMD64). My issue is that my primary monitor does not wake up (logs show the monitor as disconnected) after the system resumes from suspend-to-RAM. I am using GNOME as my DE but I was able to reproduce the issue in KDE and Cinnamon. I am using an Nvidia GTX1070 GPU with the proprietary nvidia-drivers (375.66) package. Unfortunately, the nouveau drivers do not even allow me to resume from suspend-to-RAM. I can resolve the issue by logging out of my user session. As soon as I get back to GDM, both monitors work. Logging back into the same user account restores the Acer as the primary display.
I am using two monitors - the primary is an Acer XB271HU (2560x1440, 144Hz, IPS, G-Sync) and the secondary is a Dell U2713HM (2560x1440, 60 Hz, IPS). After resuming from standby, only the Dell monitor is used. Both monitors are connected via DisplayPort. The Acer is shown on DFP- 2 and the Dell on DFP-4. While both monitors are connected via DP, the Acer uses 4 lanes @ 5.4Gbps while the Dell uses 4 lanes @ 2.7 Gbps, presumably due to the higher refresh rate on the Acer. Given that the issue persists with 3 different DEs, I suspect the problem is either a bug with the Nvidia drivers or a configuration issue, but I'm not sure what to do next. The Xorg log indicates no seemingly relevant errors. However, both the Xorg log and xrandr show the Acer monitor as disconnected after resuming from suspend. For example, where it would previously show: [ 99312.524] (--) NVIDIA(GPU-0): Acer XB271HU (DFP-2): connected [ 99312.524] (--) NVIDIA(GPU-0): Acer XB271HU (DFP-2): Internal DisplayPort [ 99312.524] (--) NVIDIA(GPU-0): Acer XB271HU (DFP-2): 1440.0 MHz maximum pixel clock After suspending to RAM, I see: [ 66519.291] (--) NVIDIA(GPU-0): DFP-2: disconnected [ 66519.291] (--) NVIDIA(GPU-0): DFP-2: Internal DisplayPort [ 66519.291] (--) NVIDIA(GPU-0): DFP-2: 1440.0 MHz maximum pixel clock When the Acer monitor is working, xrandr shows the following output: DP-0 connected primary 2560x1440+0+0 (normal left inverted right x axis y axis) 598mm x 336mm 2560x1440 59.95 + 144.00* 120.00 99.95 84.98 23.97 1024x768 60.00 800x600 60.32 640x480 59.94 I thought the issue might be the higher refresh rate so I tried reducing the Acer to 60 Hz but that didn't resolve the issue. Disabling G-Sync in the Nvidia control panel doesn't seem to have any impact as the monitor still displays G-Sync mode (variable refresh rate depending on content), and there is no way to turn this mode off from the monitor. I am able to toggle G-Sync on/off in Windows, so there's nothing wrong with the monitor. Here is relevant log output after resuming from suspend-to-RAM: https: //pastebin.com/9zLCA76B Thanks in advance for the assistance, Jason -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEq7ncLkwZsndhZmLWsskfuEl+i10FAllY5yEACgkQsskfuEl+ i11d+w//WxFJPE9tVBKB4Dggkpvj/yndYRpqOcaTA/5AsRk1B6ixObBJvCh3nwQt GhKJBsP1/uIDHEpKxi7w5fE1GKLVm8qPI+lrR9TTheL76mNEpufFOh//TV30sBub mdKaGzBJhp5gW2b6Gxa4MAIYnkSDALsQkcC05MVvIIO7ETTHgMDSGrVYp2DP6Kxn rjuOgkfjP+A6NdVNdp1dsplVYMV+bqXOaEk0/z1OEzzJhlJ14WqRKmcvpWl6g0ff iWx67fcajjbwDINWI+KwCuBufWnd0FR4X8A9GCSl/EfUn4XqxT3OmGKZeFN9NLyc xZfQjdHkArOCZyfyDgHrnOFMAZLudPPuL0k3wqMBEElt/TMnGEe4I98qzaVpwqeA 8GCO3jzeZm6WIBkHk9jNmzrXAvclQ2ZDnHswkD3JHi+UWBUf6U83mwNeRSJFQH6G rSPXpF4fcotYDXvWCLlKVIZDuoXVeVznNkrEZlE721t1Gd04gn5XdlGIBSvZ0T6H E6CYZyFooe+qeFufueaYm+i2kkII68ZBJb4A7wJJSHxoG+ByRBZSkqMNetmf6wAb HqCKm/m7Qn/gKRyJS9srcul8zQgYjcaOQUWP3z8HiUHFWO6LIJ4M3SIoSkE1m5qU PSWXCjArUESc5PoiSYJt3cnlTc6hUqj+agMSxOxwtItDmgEs9dk= =yQqv -----END PGP SIGNATURE-----
